Improved #290 - Open Containing Folder menu.

No longer show the option for Open Containing Folder when we cannot do this
action, therefore also hide the command.

Reusing existent ID for opening containing folder. Moved code to ViewCommands
[Ide] TypeSystemService now shares a serializer instance to save some
memory.
[Ide] Lock shared serializer.
AFAIK the serializer isn't thread safe yet - but should be called most
of the time from the same thread anyways.
Merge pull request #292 from Therzok/enabledToVisible

Improved #290 - Open Containing Folder menu.
[TextEditor] Added workaround for broken Gtk.TreeView.GetTooltipContext
Remove unused class and icons
[NUnit] Add support for custom console runners

The TestRunnerExe project property can be used to specify the path to a
custom nunit-console implementation to be used for running the tests.
1. Add support for KDE and konsole terminal
2. Add Methods for folder opening in terminal
3. Set default Shell to xterm
Fixed 'Bug 12439 - Error from resolve command handler '.
[Ide] Fixed some obsolete warnings from monodoc.
[Ide] Fixed small issue in xml documentation lookup.
Fixed 'Bug 12433 - Cast warnings when implicit casts exist'.
Revert "[Ide] Fixed small issue in xml documentation lookup."

This reverts commit 7f2e6e309c3747e74d3843ed6254cace2ab4a3c1.
Revert "[Ide] Fixed some obsolete warnings from monodoc."

This reverts commit 38af572ab3dae39bde87c17bf67f6dfd90d43a11.

It doesn't work w/ the MonoDoc shipped in Mono 2.10 and for .NET.
Fix execution of single tests when using a custom runner
Revert "Remove unused class and icons"

This reverts commit f64541a37fe3c8fd8ba92a39ede06c352861641b.
[Ide] Get rid of annoying combobox resize on startup
[Ide] Don't swallow/log exceptions in ApplicationService.Run

Leave that up to callers.
[mdtool] Always log fatal errors
bumped md-addins for various iOS fixes