add options_for_select

add method `options_for_select` from Rails.
add rails callbak methods
change abbreviation to c for controller
respect the  convention
use m as prefix and fix conflicts with other snippets
Merge pull request #320 from wongyouth/add_rails_methods

Add rails callback methods
Allow java else/elif to be expanded mid line.
Merge pull request #326 from RyanPineo/master

java: Allow else/elif to be expanded mid line.
Scala snippets fix
Update python.snippets

adding code encoding.
Merge pull request #327 from ches/fixes

Scala snippets fix
Merge pull request #328 from hallaj/master

Update python.snippets
Merge remote-tracking branch 'upstream/master'