[Scenario] Refactor dependency out of tag selection dialog

Report results passively in tag selection dialog added in
support of nasa/MCT-Plugins#129; this allows removal of
the explicit reference to the type ActivityVisualControl,
permitting reuse of the tag selection dialog in other
contexts (specifically, from the Create dialog, in order
to provide functionality for nasa/MCT-Plugins#133)
[Scenario] Add types & tags to activity creation UI

Add buttons (non-functional) for settings types and tags
to the activity creation UI. Additionally, perform some
clean-up on the layout of components within this dialog.
[Scenario] Layout for activity create dialog's message

Adjust dialog layout for activity create wizard such
that fields are more evenly spaced, and changes to
message (e.g. when name is left empty) do not disrupt
layout.
[Scenario] Give repository info to Activity wizard

Provide information about relevant repositories
(Activity Types, Tags) to the Activity creation
wizard upon instantiation; this will permit
subsequent creation of appropriate tag selection
dialogs.

Additionally, this is useful for programmatically
populating the wizard's UI itself (based on
relevant repositories, rather than hard coded.)
[Scenario] Show tag selectors from Activity wizard
[Scenario] Make tag/type associations in Activity wizard

Add tag/type associations selected using tag selection
dialogs to the created Activity, from the Activity
wizard. This completes introduction of functionality
for nasa/MCT-Plugins#133.
[Scenario] Add method-level doc to TagSelectionDialog
Merge pull request #141 from VWoeltjen/mctPlugins133

[Scenario] Allow user to specify types & tags from Activity wizard