Parallelize unit test runs
Parallelize unit test runs

By default the xUnit console runner will run test assemblies one at a
time, but within a test assembly run test collections in parallel. Here
we update BuildAndTest.proj to both run the assemblies in parallel, and
the collections within the assemblies. This shaves a couple of seconds
off of the run time.

genlu/roslyn-analyzers,mavasani/roslyn-analyzers,jaredpar/roslyn-analyzers,heejaechang/roslyn-analyzers,tmeschter/roslyn-analyzers-1,srivatsn/roslyn-analyzers,SpotLabsNET/roslyn-analyzers,mattwar/roslyn-analyzers,jasonmalinowski/roslyn-analyzers,pakdev/roslyn-analyzers,jepetty/roslyn-analyzers,jinujoseph/roslyn-analyzers,mavasani/roslyn-analyzers,qinxgit/roslyn-analyzers,VitalyTVA/roslyn-analyzers,bkoelman/roslyn-analyzers,pakdev/roslyn-analyzers,modulexcite/roslyn-analyzers,Anniepoh/roslyn-analyzers,natidea/roslyn-analyzers,dotnet/roslyn-analyzers,dotnet/roslyn-analyzers