workflows: widget to action name change
- NOTE Changes the naming of Holding Pen "widgets" to "actions" to more clearly distinguish these UI elements from widgets elsewhere in Invenio. The name "action" better suits these types of components which is representing an action that needs to be taken by operators.
- Renames several files to make use of this new naming strategy.
Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>