"strict" option for startItemPageEditMode in entityview

In some cases, only the event origin's toolbar shall remain enabled when starting edit
mode (e.g. reference toolbars shall be disabled when starting the claim's edit mode).
However, regarding some other edit mode(s), toolbars that are sub-elements of origin
shall remain enabled as well (e.g. adding/editing references).

Change-Id: Iab2b61da135685bea8905087e467776cbe116122
Merge ""strict" option for startItemPageEditMode in entityview"