Bug 572883: Pattern Viewer in Templates pages should support copy

- Add the action 'Select All' and 'Copy' to the context menu of the
  pattern viewer on the 'Templates' view.

Also:
- Set ActionDefitionId to the action on the templates preference page
  and on the edit templates dialog so that the key bindings are shown
  in the context menus.


Change-Id: I56c24ac1ea0ac1b7f3101f267ba201b6d0904009
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.text/+/179385
Tested-by: Platform Bot <platform-bot@eclipse.org>
Reviewed-by: Sebastian Ratz <sebastian.ratz@sap.com>
Reviewed-by: Matthias Becker <ma.becker@sap.com>
4 files changed