[Save All] Move getAllModifiedObjects to capability

Moves getAllModifiedObjects to a capability.
This simplifies AbstractComponent API (this
method is rarely overridden; only one plug-in
uses this behavior) and gives some flexibility
to handling of modified objects to those
plug-ins. Supports nasa/MCT-Plugins#72
[Save All] Move Save All notification to capability

As with getAllModifiedObjects, move
notification of a successful Save All
to a capability in order to further
simplify AbstractComponent with regard
to the rarely-used Save All functionality.
[Save All] Notify work unit delegate on save

A work unit delegate may also be responsible
for managing the aggregation of dirty objects
in support of Save All, so notify it when a
component has been saved.
[Save All] Merge latest from master
[Save All] Back explicit object manager map

Use a map of id to component to track modified
objects in the explicit object manager. This
means that if multiple versions of the same
component are explicitly added as modified
objects, only the latest is actually returned
in a subsequent getModifiedObjects. This
avoids Save All ambiguities in cases where
multiple versions of the same object are
returned in getModifiedObjects.
Merge branch 'master' into mctPlugins72
[Save All] Test ObjectManager implementations
[Save All] Amend test to increase coverage
Merge pull request #206 from VWoeltjen/mctPlugins72

[Save All] Move getAllModifiedObjects to capability