QEP 2: Enhanced Array Literals

[bamarsha]

This issue tracks the implementation of QEP 2: Enhanced Array Literals. The feature branch is feature/qep2.

• Support the empty array constructor, [] (Miscellaneous changes for HM type inference and QEP 2 #884)
  • Add Hindley-Milner type inference module (Add Hindley-Milner type inference module #917)
  • Replace existing type inference with Hindley-Milner (Use HM inference in expression and statement verification #940)
  • Update usages of obsolete range fields in QsTypeParameter and UserDefinedType (Update use of deprecated range field in UserDefinedType and QsTypeParameter #952)
• Support the repeated constant array constructor, [x, size = n] (Add "[value, size = n]" array constructor #856)
  • Support [x, size = n] in attribute arguments (Miscellaneous changes for HM type inference and QEP 2 #884)
• Add SizedArray to NamespaceManager.fs (ExpressionHash) and QsharpCodeOutput.cs (Handle SizedArray in code output and optimizations #963)
• Update optimizations for SizedArray: ConstantPropagation.fs, Evaluation.fs, HelperFunctions.fs (isLiteral) (Handle SizedArray in code output and optimizations #963)
• Address issues from bug bash (Improve HM type inference diagnostic messages #980)

Deferred:

• Deprecate the new Type[n] array constructor (Deprecate new array expression #956)
• Update QIR generation for SizedArray expression kind