Entries are being duplicated as described in

* https://github.com/saltstack/salt/issues/60220 and
* https://github.com/saltstack/salt/issues/59785#issuecomment-826590482

Fix failure highlighted on OpenSUSE Tumbleweed, where the `cmd.run` runs
before the `pkg.installed`:

* https://gitlab.com/saltstack-formulas/nginx-formula/-/jobs/1345325819#L2830

nginx.servers_config wants a lightened copy of the nginx map
to render as json; but, when it was trying to remove the
servers and snippets keys from the map it assumed their presence,
causing a KeyError if they were not present by its use of .pop().

While wrapping these in an "if" clause would likely be more
correct, along with replacing .pop() with del (if jinja even
supports that) the simplest change here is to just specify a
default value for .pop(), which obviates the KeyError.

Fixes #274

Also, check config before applying

* servers_config should run without service dependency. Service is
  managed in servers.sls.
* dropped nginx_service_reload in favor of extending nginx_service
* wait for all file states (create and delete)
* create dirs for symlinked files

* Automated using https://github.com/myii/ssf-formula/pull/302

* correctly set dependencies in configuration
* update RPM repo key
* add tests for passenger installation as nginx module
* update test matrix

* Automated using https://github.com/myii/ssf-formula/pull/237

* Checked using https://github.com/myii/ssf-formula/pull/131

* Close #261
* https://nginx.org/en/docs/ngx_core_module.html#worker_connections

* Close #241

```bash
Examining nginx/pkg.sls of type state
[201] Trailing whitespace
nginx/pkg.sls:149
    - gpgcheck: 0
```

```bash
Examining nginx/map.jinja of type state
[202] Jinja statement should have spaces before and after: {% statement %}
nginx/map.jinja:175
})%}

[202] Jinja statement should have spaces before and after: {% statement %}
nginx/map.jinja:181
})%}

[202] Jinja statement should have spaces before and after: {% statement %}
nginx/map.jinja:188
})%}

[202] Jinja statement should have spaces before and after: {% statement %}
nginx/map.jinja:192
    })%}

[202] Jinja statement should have spaces before and after: {% statement %}
nginx/map.jinja:195
    })%}
```

```bash
Examining nginx/certificates.sls of type state
[206] Jinja variables should have spaces before and after: {{ var_name }}
nginx/certificates.sls:40
    - contents_pillar: {{salt['pillar.get']('nginx:certificates:{}:public_cert_pillar'.format(domain))}}

[202] Jinja statement should have spaces before and after: {% statement %}
nginx/certificates.sls:47
{% if salt['pillar.get']("nginx:certificates:{}:private_key".format(domain)) or salt['pillar.get']("nginx:certificates:{}:private_key_pillar".format(domain))%}

[206] Jinja variables should have spaces before and after: {{ var_name }}
nginx/certificates.sls:54
    - contents_pillar: {{salt['pillar.get']('nginx:certificates:{}:private_key_pillar'.format(domain))}}
```

* Automated using `ssf-formula` (v0.6.0)

* Automated using `ssf-formula` (v0.1.0-rc.2)

- currently you're forced to define extra states if you opt to install nginx with passenger,
 if you want the same outcome for passenger and nginx installs with equivalent config
- passenger is an extra module on top of nginx, makes no sense to end up with less configuration by default

(...) for snippets filename.
BREAKING CHANGE: Users have to modify their pillar
according to this commit. Users MUST append '.conf' for their
existing managed snippets.

First implementation of TOFS for:
nginx_config, passenger_config, servers_config and snippets
Introduced tplroot on modified files as well
Fixed GH link of nginx.conf file in docs/TOFS_pattern.rst
Fixed test for snippets name pillar

* Route all to `nginx/deprecated.sls`

BREAKING CHANGE: all previous `nginx` based configurations must be reviewed;
`nginx.ng` usage must be promoted to `nginx` and any uses of the original
`nginx` will have to be converted.

With this one can now also write

 - include:
   - file1
   - file2

Rather than only

 - include: file1
 - include: file2

on openSUSE Leap 15.0, the string was systemd.cpython-36

like openSUSE and SLES

to reduce duplication of constants