Amend Git update command to ensure already-initialized extensions are updated

See answer and comments at http://stackoverflow.com/a/10168693/513536
Merge pull request #2057 from DavidOliver/git-update-extensions

Amend Git update command to ensure already-initialized extensions are updated
Better check for development versions
Update jQuery to 2.1.1
Merge branch 'integration' of github.com:symphonycms/symphony-2 into integration
Release 2.4
First lot of code formatting done, phew!
Last lot of code formatting to PSR-2
Missed a bit
Merge pull request #2072 from symphonycms/psr-code-standard

Move the codebase to PSR-2
Correct syntax error
Fix error observed in PHP 5.4.28; sprintf failed when using double quotes

Using double quotes, the params we're being pre evaluated by php before sprint got to replacing them, and a fatal error occurred.
Add Manager restrictions for Extension navigation. Fixes #2058
Abstract the creation of Error nodes in Events
Added Code Climate badge
Update for 2.4.1 beta
Remove old backwards compatibile Datasource/Event files from Symphony 2.2.x
Merge branch 'integration' of github.com:symphonycms/symphony-2 into integration
Simplify the migration upgrade function with late static binding
change Symphony version in the .htaccess template