Fixes to support distributed scenario

Added parameter for TestController to allow agents to connect to remote host
-Using CmdLine package to simplify argument parsing #17 

Catching exceptions from Json serializer that caused agent to crash when worker trace messages are written to standard output

Using thread-safe collection for worker connections

Force copy of Microsoft.Web.Infrastructure.dll to run TestController app on full IIS - Not GAC'd
@abnanda1 @davidfowl 
The DeserializeObject call blows up when the worker's SignalR clients write trace messages to standard output. When we tried sending these messages back to the TestController, the agent was crashing (I presume due to some kind of concurrency issue).
Switching to Streamer should eliminate the need to deal with these exceptions, but there is still the question of what to do with the client trace information.