Cleanup of framework's use of @package and @subpackage labels and additional of labels for classes missing packages.
Moved all GridField related components to the one name.
Countless spelling fixes, grammar for other comments.
Link ClassName references in file headers.
MINOR Parameter namespacing for GridState to avoid clashes with multiple GridField instances in same form
MINOR GridField->index() to render the field, unify with gridFieldAlterAction() to support state changes
API CHANGE: Simplified state handling so that it's just a key store. Affectors are replaced with GridField_ActionProviders. API CHANGE: Removed GridField state manipulation actions instead opting for GridField_ActionProvider actions.
API CHANGE: Removed support for modifiers that add "body" rows, instead having core support for generating the body rows hardcoded into the GridField.
API CHANGE: Allow modification of columns across the whole GridField with the GridField_ColumnProvider interface.
API CHANGE: Renamed GridField_AlterAction to GridField_Action, and added actionName/args parameters, since it can be used for all actions (including batch actions and row actions)
API CHANGE: Removed GridFieldRow class.