Merge pull request #67 from ddur/master

CodeCoverage fixes.
Update string resources.
Update setup for new OpenCover files.
Fix interaction between "Hide cursor while typing" and InsertWithCursor().
Update mouse cursor in InsertWithCursor() mode.
Remove "allow overstrike" option.

I don't think we should have this in our options dialog. Having too many options just is unnecessary complexity, both for users and when testing.
Move InsertionCursorLayer to its own file.
Add ParserService.ResolveContext() method.
Replace null with ErrorResolveResult.UnknownError instead of throwing an exception.
Update to NRefactory commit ef1a5d63.

ef1a5d6 Fixed a potential null reference exception in completion.
6188c05 Fixed bug in name proposal completion.
a8a5ed1 Fix NullReferenceException in code completion.
cef9a79 Fix file headers.
0ecb7f4 Fixed bug in CS0169FieldIsNeverUsedIssue
552443a Implemented 'CS0169FieldIsNeverUsedIssue'.
cdfcc33 Added new formatting option: "SpaceBeforeSemicolon".
Render InsertWithCursor line in the middle of empty lines, but between lines if they are not empty.
fix #336: Implement interface in code-behind .xaml.cs tries to insert interface implementation in .xaml file
Merge pull request #335 from ddur/master

CodeCoverage again