Added a subcontainer tag class param so classes can be added to the subcontainer ULs
Cleaned up logic for the container class and added subcontainer handling to render collapsible.
Merge branch 'develop' of git://github.com/daylightstudio/FUEL-CMS into develop

# By David McReynolds
# Via David McReynolds
* 'develop' of git://github.com/daylightstudio/FUEL-CMS:
  fixes for when the module data is set to be displayonly
  fix for custom field post_processing methods when using a block field type
  fixed image uploading issue and using placeholder values
  added post_process_saved_values to fix issues with image uploads and changing placeholder values
  fixed errors in Fuel_tags class
  fixed issue with Form_builder's diplayonly fields when being rendered with divs instead of a table as well as when an array value is set
  fixed Form class to return an empty string if the value passed to the prep function is an array
  fixed issue with inline_edit field type
  fix for displaying mutl-language site page variables
  minor Menu comment documentation update
  fixed error if fuel_mode is set just to "cms"
  Added disabled parameter to Form_builder::create_text method
Added _handle_where() method to process db::where & db::where_in
Merge pull request #227 from specialbrand/develop

Added a subcontainer tag class param so classes can be added to the subcontainer ULs