Added IDynamicMemberReferenceExpression

Move feature/ioperation branch to latest analyzers package

* Adding ioperation tests for ForloopStatement

* Addressing the feedback

Merge master to features/ioperation

Preserve leading directives when removing an unused variable.

Merge dev15.3.x to master

# Conflicts:
#	build/Targets/Versions.props
#	src/VisualStudio/Core/Test.Next/VisualStudioTest.Next.csproj
#	src/Workspaces/CoreTest/ServicesTest.csproj
#	src/Workspaces/CoreTestUtilities/WorkspacesTestUtilities.csproj

Better handle null literal arguments when determining what parameter to add to a constructor.

Merge conflict fixes

* dotnet/features/ioperation:
  Changing the IOperation unit test dumper to visit certain operation explicitly. (#20944)

Bump the version to 2.3.2

Crash on dispose

* Changing the dumper to get of calling base.Visit when not needed

* Getting rid of cobyrc file

* Adding copyright header

* fixing merge conflict

* dotnet/features/ioperation: (134 commits)
  Fix build break in IOperation feature branch
  Fix unit tests that broke with previous commit
  Address PR feedback from Chuck
  Fix unit test
  Add IOperation support for variations of object creation expressions (type parameter, nopia and dynamic)
  Remove dead code from GenerateConstructor.
  Disable NETCore version check
  Fixed review notes.
  Add comment
  Disable NETCore version check
  Show modifier/method/type block declaration keywords after attribute lists
  Improve type argument list parsing in error conditions. (#19467)
  Don't report modifier errors while parsing. (#16339)
  Fix assert and merge
  Remove extra space
  Restore failure behavior.
  Simplify implementation of parsing constraints. (#16429)
  Fix csproj
  Remove CapturedVariablesByLambda (#20878)
  Remove testing wait
  ...

Add a feature that offers to add missing accessibility modifiers.

Merge dev15.3.x to master

Add IOperation support for variations of object creation expressions …