Add NUnit parallelism comment to AssemblyInfo.cs

Author: Byron Delgado

Src/Properties/AssemblyInfo.cs

@@ -15,6 +15,7 @@
 [assembly: AssemblyCopyright("Copyright © Microsoft 2017")]
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
+//NUnit to allow parallelism
 [assembly: Parallelizable(ParallelScope.Fixtures)]
 
 // Setting ComVisible to false makes the types in this assembly not visible