Finishing up installation changes

* Added php web server option
* Used @stable for downloading Symfony
* Updated things since parameters.yml lives in .gitgnore by default and there is also a paramters.yml.dist file
* umask exists as a comment on the 2 files
Updating routing:

1) added section to change pattern to path. As of this recording, the old SensioGeneratorBundle is still
   the newest, so it generates with pattern.

2) Fixed some bad code-blocks with wrong variable names
Reminding people to remove the debug code
Updating the controller chapter - no real changes (yay!)
Adding the PHPStorm Symfony plugin spot
Adding a few more headers
Updating Twig - no real changes, just clarifying some code blocks!