Simplified toolbarcontroller.definition

This change set greatly reduces the toolbarcontroller mechanism.
Most of the toolbarcontroller.definition options are removed reducing the ways to defined
a toolbar for the toolbarcontroller to one. Special combinations of widget name with other
options are dropped which moves some logic into the particular definitions. (The resulting
code duplication shall be dealt within some upcoming change.)
Along with this change, the addtoolbar's "eventPrefix" option has become obsolete and is
removed.
Instead of on the node the toolbar is initialized on, now, the event handlers are
initialized on the toolbarcontroller's node simplifying the toolbarcontroller's management
mechanics (some optimization will be done in some upcoming change).

Change-Id: I8722996765273eb1dac105583008d88d5585050c
Merge "Simplified toolbarcontroller.definition"