Fix examples

If there is no namespace declared in the example, the backslash before the class name is not necessary and can be confusing
Use language independent permalinks for php.net urls

@see http://php.net/urlhowto.php
Add paragraphs about two global usergroups
Merge pull request #496 from jrfnl/Global-usergroups

Add paragraphs about two global usergroups
Merge pull request #492 from jrfnl/Use-php-net-permalinks

Use language independent permalinks for php.net urls
Merge pull request #493 from jrfnl/Adjust-examples

Adjust examples
Fix highlighter consistency

- in some places php would not be highlighted as the `<?php` tag was missing
- in one place there was a duplicate `<?php` tage
- replaced `bash` with `console` for better highlighting
- ensured all console snippets are wrapped within highlighting code
- wrapped ini examples in highlighting code