First cut on highlighting usage
Add navigation bar setting

- [x] Add docs
- [x] Allow users to turn the feature on and off
Merge remote-tracking branch 'upstream/master'
Adapt builds
Upgrade to FSharp.Compiler.Service 0.0.17

FSharp.CompilerBinding is updated to
6f731e238a169989b99a9df2d179e53bad7b9f5a commit.
Simplify HighlightUsageTagger

1. Remove unnecessary private members
2. Add warning on unused variables
xml doc is generated after "/// <" is entered
xml doc is generated after "/// <" is entered (finished)
add more test cases for XML Doc
make XmlDocComment.isBlank more robust
add XMLDoc tests
Update generated documentation for version 0.1.1
Merge pull request #19 from vasily-kirichenko/xml-doc

XML doc comments are generated as the first '<' char in a blank "///" comment is entered
Updates for highlighting usage

1. Fix inconsistency when member ranges are longer than expected
2. Fix lastIdent advanced one character too far on array access
3. Add async GUI
5. Remove unnecessary locks
6. Add a switch to disable the feature
Improve project system and add tests
Use project parser from FSharp.Autocomplete
Fix bugs

1. Filter by file name in order to get ranges safely
2. Fix reference paths so that type checking has no errors
3. Highlight long (fully-qualified) identifiers
4. Use similar color scheme as C#
Bug fixing

1. Fix off-by-one on getting ranges
2. Use automatically-resolved project references
Merge pull request #16 from dungpa/master

Add highlighting usage
Prepare for release

Make highlighting more robust wrt exceptions