Lots of small UI fixes. (...)

- Fixed plugin/service names not shown in ConfigurationManager editor.
- Exceptions thrown by GraphX are now caught, and will cause the graph to reset to CompoundFDP layout instead of breaking.
- Cleared up old IPluginInfo.PluginID references.
- Edition of service/plugin properties are now completely disabled while the engine is running.
Lab: ConfigurationManager bugfixes.

- Small DRY in MainWindow.xaml.cs.
- IYodiiEngineResult.Describe() extension can now be read by humans (hopefully).

Fixed:
- Creating/destroying multiple ConfigurationManager editor window and changing ConfigurationManager content causes reentrancy.
  * Caused by multiple ViewModels still lingering (and bound) to SelectionChanged. Fixed by disposing those on close.
- Changing configuration while engine is running causes NREs.
  * Caused by unset Configuration errors in result. Fixed by using Describe() instead.
Lab: Added running indicators.
Interface wrapping for live plugins/services.
Lab: Added Export to PNG button
Merge remote-tracking branch 'origin/f-yodii-commands' into feature/engine-integration
Merge remote-tracking branch 'origin/feature/engine-integration' into f-yodii-commands
Fix typo.
Merge remote-tracking branch 'origin/f-yodii-commands' into f-yodii-commands
Fixed terrific stop bug...