Toggle edit inline

Added an edit_inline_available option (default: true) to the grid panel to disable cell editing.

Both edit_inline_available and edit_in_form_available: functionality unchanged
Only edit_inline_available: functionality unchanged

Only edit_in_form_available:
- "Add In Form", "Edit In Form", Apply actions are removed from bbar/context menu
- Add and Edit actions call their form versions
- Cell editing plugin is removed from the grid
- Double-clicking an item in the grid calls the onEditInForm handler