Tweak grid in order to use the store's autoSync option

By default the Ext JS store calls the get_data endpoint. To use the
autoSync option, the sync event gets cancelled and calls the onApply
method instead.
Lock rspec to the newest version
Fix for SearchPanel field names
Merge pull request #94 from scho/grid_auto_sync

Tweak grid in order to use the store's autoSync option
Merge remote-tracking branch 'upstream/master'
Merge pull request #95 from scho/master

Lock rspec to the newest version
Rewrite grid_with_action_column.feature with mocha specs