TestFx STA Extension

STA extension for MSTest framework and adapter
Adds the ability to run tests in STA thread for unit tests that depend on COM, OLE and UI components.

Usage 1:

[STATestClass] // Runs all tests [ test1, test2, test3 ] in this class in STA thread
public class SampleTestClass
{
    [TestMethod] 
    public void Test1 () {....}
    [TestMethod]
    public void Test2 () {....}
    [STATestMethod] // Using STATestMethod inside a class which is already marked STA is redundant
    public void Test3 () {....}
}

Usage 2:
```C# [TestClass] // Runs all tests except Test3 in this class as MTA public class SampleTestClass { [TestMethod] public void Test1 () {....} [TestMethod] public void Test2 () {....} [STATestMethod] // Class is NOT marked as STA - so only this method runs in STA - above tests run in MTA public void Test3 () {....} } ```