More style related warnings

[snigel]

These are just suggestions. Feel free to close or disregard if it's invalid.

Currently the linter warns about incorrect indentation levels and trailing spaces. I've been looking at example configurations from nginx to see if there is some common style guidelines that could be added.

1. One space before the opening brace.

events {
   worker_connections  4096;  ## Default: 1024
}

Warn when it isn't.

events{

2. One space between if parameters.

if ($true) {
    add_header X-First 1;
}

Warn when there are multiple spaces.

if ($true) {
     add_header   X-First   1;
}

3. Comments uses space.

# A comment.

Warn when it itsn't

#A comment.

4. One newline between blocks

  upstream big_server_com {
    server 127.0.0.3:8000 weight=5;
  }

  server { # simple load balancing
    listen          80;
  }

Warn when there are none or multiple:

  upstream big_server_com {
    server 127.0.0.3:8000 weight=5;
  }
  server { # simple load balancing
    listen          80;
  }

  upstream big_server_com {
    server 127.0.0.3:8000 weight=5;
  }



  server { # simple load balancing
    listen          80;
  }

5. location regexes should use space between modifier and regex.

location ~* ^/if-and-alias/

Warn:

location ~*^/if-and-alias/

The example without space currently produces another warning, see #24