Remove the DefaultTraceListener if there is a hostTraceListener.

#2260
Fixed build
Fix build & update to latest ajax min
- #2310
Initial changes to support sending to multiple signals in one go.
- Added Signals everywhere there was Signal
- Added MultipleSignalProxy which is a client proxy for sending to multiple signals.
- Redesigned how we pass state to proxies.
- Cleaned up duplication for the HubConnectionContext by introducing HubConnectionContextBase
- Added Clients and Groups methods to IHubConnectionContext
- Added overload to Groups.Send that takes multiple group names.
- Fixed group manager tests.
- Added hub tests for new API surface.
- Added tests for persistent connection.
Make Signals private set
Delete minified signalr JS client from repo

Conflicts:
	samples/Microsoft.AspNet.SignalR.Samples/Scripts/jquery.signalR.min.js
Fixed package sources
Added connection data (hub subscriptions) to every request.

- This also involved moving the starting event above the negotiation logic instead of inside, this way connection data is built before the negotiate request.

#2145
Added tests to verify that connection data is passed with all requests.

- This also involved adding a ConnectionDataVerifierHub which checks requests to ensure that all requests contain the correct information associated with them.

#2145
Addressed code review comments.

- This involved combining the addQs and addConnectionData into a singular method (prepareQueryString).
- Also modified addConnectionData to be private amongst the common js file.
Merge branch 'release' into dev

Conflicts:
	.nuget/NuGet.targets
	samples/Microsoft.AspNet.SignalR.Samples/Scripts/jquery.signalR.min.js