Correct the order of parameters to Version

Make RunCsc/Vbc scripts respect DOTNET_HOST_PATH

Merging on behalf of @svick 
Thanks for the contribution!

Multi-target change cleanup

Suppress IDE0004 for switch case label when casting is required

Changes BuildBoss to enforce portable test projects use the
UnitTestPortable label. Probably going to remove that in the near future
but at this point it's still required.

Fixes #21136

Updating visual studio references

* Rename Foo to Goo

* Rename ifoo to igoo

* Add back BOMs

Remove InvocationReasons enum boxing

Use multi-targeting to expose compilation primitives

Merged on behalf of @brianhartung. Thanks!

This is related to https://github.com/dotnet/cli/pull/7311

Merging on behalf of @megafinz. Thanks

Use explicit casts rather than `as`

Rewrite CryptoBlobParser to use BlobReader/BlobWriter instead of casts

Fixes #20693

Add user facing option to place blank lines between using/import groups.

Merge dev15.3.x to master

# Conflicts:
#	src/EditorFeatures/TestUtilities/Remote/WatsonReporter.cs
#	src/EditorFeatures/TestUtilities/ServicesTestUtilities.csproj
#	src/VisualStudio/Core/Next/Remote/JsonRpcClient.cs
#	src/Workspaces/CSharp/Portable/CSharpWorkspace.csproj
#	src/Workspaces/Core/Portable/Workspaces.csproj
#	src/Workspaces/VisualBasic/Portable/BasicWorkspace.vbproj

Lambda analysis uses a lot of pooled data structures (as it should,
since it will be redone from scratch using the exact same structure for
every method) but did not properly free everything. This should properly
recursively free all pooled data structures used in analysis.

Correct badge icon URLs to reflect renamed builds in DotNet's Jenkins CI