Add initial LanguageInfo and BraceExtractor for PowerShell
Cannot highlight PowerShell command names
Moved string escape sequence extractor for C-based languages into own class
Remove hard-coded string escape sequence parsing from KeywordTagger and use the new model
Add initial code for PS escape sequence parser
Implement basic powershell string escape sequence parsing and tests
Add new tests for PsEscapeSequenceParser
More tests and implement single quoted here string support
Add field to CharPos to store extractor state
Need to propagate extractor state to BracePos as well
Rename PSBraceExtractor to PsBraceExtractor
Adding initial tests for PowerShell Brace Extractor
Remove state from char/brace pos objects for now
Adding options page for PowerShell
Fix list of control-flow keywords in PowerShell
Merge branch 'powershell' into develop