* Automated using https://github.com/myii/ssf-formula/pull/207
* Use `bionic` for Travis (also no longer need to use `pip3`)
* Add `without-ipv6` suite, to avoid errors with `ip6tables` such as:

```
[ERROR   ] stdout: ERROR: initcaps
[Errno 2] ip6tables v1.8.4 (legacy): can't initialize ip6tables table `filter': Table does not exist (do you need to insmod?)
Perhaps ip6tables or your kernel needs to be upgraded.
```

* Automated using https://github.com/myii/ssf-formula/pull/191

* Automated using https://github.com/myii/ssf-formula/pull/167

* Automated using https://github.com/myii/ssf-formula/pull/124

* Automated using https://github.com/myii/ssf-formula/pull/112

* Automated using https://github.com/myii/ssf-formula/pull/107

* Automated using https://github.com/myii/ssf-formula/pull/106

* Automated using https://github.com/myii/ssf-formula/pull/100

* Automated using https://github.com/myii/ssf-formula/pull/98

* Automated using https://github.com/myii/ssf-formula/pull/97

* Automated using https://github.com/myii/ssf-formula/pull/90

* Automated using https://github.com/myii/ssf-formula/pull/86

* Automated using https://github.com/myii/ssf-formula/pull/89

* Automated using https://github.com/myii/ssf-formula/pull/84

* Automated using https://github.com/myii/ssf-formula/pull/80

* Semi-automated using https://github.com/myii/ssf-formula/pull/60

* Automated using https://github.com/myii/ssf-formula/pull/40

* Automated using https://github.com/myii/ssf-formula/pull/27

* Automated using https://github.com/myii/ssf-formula/pull/22

* Automated using https://github.com/myii/ssf-formula/pull/23

* Semi-automated using `ssf-formula` (v0.5.0)
* Fix errors shown below:

```bash
ufw-formula$ $(grep "\- yamllint" .travis.yml | sed -e "s:^\s\+-\s\(.*\):\1:")
pillar.example
  1:1       warning  missing document start "---"  (document-start)
  3:12      warning  truthy value should be one of [false, true]  (truthy)
  7:11      warning  truthy value should be one of [false, true]  (truthy)
  12:22     warning  truthy value should be one of [false, true]  (truthy)
  64:13     warning  truthy value should be one of [false, true]  (truthy)
  69:13     warning  truthy value should be one of [false, true]  (truthy)
  77:13     warning  truthy value should be one of [false, true]  (truthy)
  84:14     warning  truthy value should be one of [false, true]  (truthy)
  101:16    warning  truthy value should be one of [false, true]  (truthy)
  106:14    warning  truthy value should be one of [false, true]  (truthy)
  110:13    warning  truthy value should be one of [false, true]  (truthy)

test/salt/pillar/default.sls
  1:1       warning  missing document start "---"  (document-start)
  2:12      warning  truthy value should be one of [false, true]  (truthy)
  9:14      warning  truthy value should be one of [false, true]  (truthy)
  12:13     warning  truthy value should be one of [false, true]  (truthy)
  15:13     warning  truthy value should be one of [false, true]  (truthy)
  19:13     warning  truthy value should be one of [false, true]  (truthy)
  25:14     warning  truthy value should be one of [false, true]  (truthy)
  29:13     warning  truthy value should be one of [false, true]  (truthy)
```

* Automated using `ssf-formula` (v0.1.0-rc.1)

* Use balanced matrix based on `template-formula` guidelines
* Initial ref: https://github.com/saltstack-formulas/template-formula/issues/118