Added UI support for copying multiple Automate objects.

- Added support to allow user to select multiple objects from list of Classes, Instances, Methods and copy them.
- Changed "copy" method miq_ae_class, miq_ae_instance, miq_ae_method models to be class methods and accepts list of ids as an array and pass them on to new copy_multiple methods to appropriate copy classes.
- Changed UI to display flash error message when a single Namespace is selected from list of Namespace/Classes to copy, and ignore any namespaces when multiple records are selected to copy.
- Added code in haml view to show list of selected objects to copy at the bottom of screen.
- Switched dynatree calls in "cfmeDynatree_activateNodeSilently" JS method to activateSilently and expand a node to get the parent node of newly copied objects to be selected in the Automate tree. Changed it to activate a node first and then try to expand the node.

Issue #221
Changed to replace flash message div and fixed typo in variable name.

- Changed to replace flash message div when field value is changed to remove previous error message from screen after field values are changed.
- Fixed name of variable being passed in to copy method for overwriting existing items.
- Fixed spec tests to set selected_items in @edit

Issue #221
Moved Replace existing items checkbox above namespace selection box.

- Changed text on Overwrite Source checkbox.
- Moved Replace existing items checkbox above namespace selection box, and changed it be always visible for Instances/Methods copy.

Issue #221
Added tests for "copy" method in Automate Class/Instance/Method models

Issue #221
Merge pull request #249 from h-kataria/ae_copy_multiple_objects

Added UI support for copying multiple Automate objects.