* Semi-automated using https://github.com/myii/ssf-formula/pull/31
* Includes:
  - Update TOFS
  - Use `bin/kitchen`
  - Use `dist: bionic` in Travis
  - Add `yamllint` and apply rules
  - Use `pillars_from_files` throughout
  - Replace EOL images in Kitchen & Travis
  - Add `develop` images in Kitchen & Travis
* Fix (or ignore)  errors shown below:

```bash
salt-formula$ yamllint -s .
./pillar.example
  1:1       warning  missing document start "---"  (document-start)
  5:23      warning  truthy value should be one of [false, true]  (truthy)
  8:25      warning  truthy value should be one of [false, true]  (truthy)
  11:25     warning  truthy value should be one of [false, true]  (truthy)
  19:21     warning  truthy value should be one of [false, true]  (truthy)
  40:89     error    line too long (108 > 88 characters)  (line-length)
  41:89     error    line too long (112 > 88 characters)  (line-length)
  43:89     error    line too long (112 > 88 characters)  (line-length)
  45:89     error    line too long (110 > 88 characters)  (line-length)
  47:89     error    line too long (89 > 88 characters)  (line-length)
  74:27     warning  truthy value should be one of [false, true]  (truthy)
  82:9      error    wrong indentation: expected 10 but found 8  (indentation)
  101:14    warning  truthy value should be one of [false, true]  (truthy)
  102:20    warning  truthy value should be one of [false, true]  (truthy)
  103:89    error    line too long (119 > 88 characters)  (line-length)
  121:7     warning  comment not indented like content  (comments-indentation)
  122:24    error    syntax error: found character '%' that cannot start any token
  310:89    error    line too long (102 > 88 characters)  (line-length)
  330:89    error    line too long (113 > 88 characters)  (line-length)
  433:1     error    too many blank lines (1 > 0)  (empty-lines)

./salt/osmap.yaml
  4:2       error    syntax error: found character '%' that cannot start any token
  6:89      error    line too long (93 > 88 characters)  (line-length)
  22:89     error    line too long (137 > 88 characters)  (line-length)
  23:89     error    line too long (134 > 88 characters)  (line-length)
  33:89     error    line too long (149 > 88 characters)  (line-length)
  34:89     error    line too long (146 > 88 characters)  (line-length)

./salt/osfamilymap.yaml
  4:2       error    syntax error: found character '%' that cannot start any token
  6:89      error    line too long (94 > 88 characters)  (line-length)
  24:89     error    line too long (149 > 88 characters)  (line-length)
  25:89     error    line too long (146 > 88 characters)  (line-length)
  39:89     error    line too long (105 > 88 characters)  (line-length)
  40:89     error    line too long (127 > 88 characters)  (line-length)
  56:89     error    line too long (101 > 88 characters)  (line-length)

./salt/ospyvermap.yaml
  4:1       warning  missing document start "---"  (document-start)

./salt/defaults.yaml
  3:1       warning  missing document start "---"  (document-start)
  7:21      warning  truthy value should be one of [false, true]  (truthy)
  8:12      warning  truthy value should be one of [false, true]  (truthy)
  9:23      warning  truthy value should be one of [false, true]  (truthy)
  10:19     warning  truthy value should be one of [false, true]  (truthy)
  14:25     warning  truthy value should be one of [false, true]  (truthy)
  15:25     warning  truthy value should be one of [false, true]  (truthy)
  16:27     warning  truthy value should be one of [false, true]  (truthy)
  17:27     warning  truthy value should be one of [false, true]  (truthy)
  39:28     warning  truthy value should be one of [false, true]  (truthy)
  41:28     warning  truthy value should be one of [false, true]  (truthy)
  45:24     warning  truthy value should be one of [false, true]  (truthy)
  49:30     warning  truthy value should be one of [false, true]  (truthy)
  54:28     warning  truthy value should be one of [false, true]  (truthy)
  63:25     warning  truthy value should be one of [false, true]  (truthy)
  68:15     warning  truthy value should be one of [false, true]  (truthy)
```

This prevents the `return` key being duplicated in the minion config by L1205

* From `salt-winrepo-ng`:
  + https://github.com/saltstack/salt-winrepo-ng/blob/master/salt-minion-py2.sls
    - Package: `salt-minion`
  + https://github.com/saltstack/salt-winrepo-ng/blob/master/salt-minion-py3.sls
    - Package: `salt-minion-py3`
* Close #411

* Prepare for selecting correct version of Windows `salt-minion` pkg

This reverts commit 2a0f4617db.

* Close #403

To match the one used by the bootstrapper. Otherwhise, we end up with two repos configured

Use py3 for latest salt version
Use Python 2 on old distros
Update Gemfile
Updated centos-6 run_command, as it does not use systemd
Added tests to verify correct package versions for all cases tested

e.g. TurnKey Linux amongst others

* All minor releases appear in an `archive` sub-directory.
* Resolves main bug in GitHub issue #364.
* Simplification of original GitHub PR #365 by @ralucasg.

Signed-off-by: Johannes Löthberg <johannes@kyriasis.com>

Remove commented version and associated comment, as we still have the same
option earlier in config with an other valid comment.

* Ensure options for formulas `git.latest` are also based on defaults

* Prevent erroneous remote tracking branch modification by `salt.formulas` #238

* Allow multiple envs to use the same gitdir for `salt.formulas`

* Ensure `gitdir` original branch is checked out after formulas `git.latest`

* Fix erroneous comment re: merging in `salt` pillar

closes #367

* Minion/returner/elasticsearch yaml read fix.

* Improved the documentation for the elasticsearch returner

* Add MacOS support; fix Issue #352

* On MacOS, only attempt download if condition

Add if salt_settings.install_packages to requisites for an attempt to download the minion package on MacOS

* Update example pillar for MacOS support

Describe how to use MacOS specific options

* Add MacOS notes

* Update README.rst

* Update README.rst

* Added quotration around globing rules

salt.gitfs.gitpython.install_from_source == False on RedHat
Not sure about other O/S'es as to what default value should be

Add quick sanity check at start of state, do not attempt to do anything unless salt.gitfs.gitpython exists to check for install_from_source within