LeMP & LLLPG: Working Really Smoothly Now

• Unveiled the Macro Reference Manual
• Added macros: includeFile (aka #include), #set (aka #setScopedProperty), #snippet (aka #setScopedPropertyQuote), #get (aka #getScopedProperty), and replacePP (replace plus preprocessing of initial parameters).
• MacroProcessorTask introduces two global-scoped Symbols, #inputFolder and #inputFile.
• Eliminated #haveContractRewriter and #setAssertMethod macros, since you can now just use #set #haveContractRewriter and #snippet #assertMethod = AssertMethod;
• Renamed on_error_catch to on_throw_catch so that it's made of keywords.
• Code contracts:
  • Introduced [ensuresFinally], which checks a postcondition in finally
  • Changed Contract Attribute error messages to match MS Code Contracts
  • Code contract attributes now support lambda functions
• Changed public interface of LeMP.Compiler to make it a bit more flexible and easier to use
• ParsingService: added global language "registration" feature.
• Loyc.Essentials: added TryGetValue extension method for IReadOnlyDictionary.
• Misc., e.g. renamed some members of Loyc.Ecs.Parser.TokenType
• Bug fix to IMacroContext: made macro dictionary fully immutable

Instructions: Please extract the zip file to its own folder. Run mono LeMP.exe --editor to try it out on Linux. To use in Visual Studio, run LoycFileGeneratorForVs.exe to install VS Custom Tool, and run LoycSyntaxForVs.vsix to install the syntax highlighter.