Be able to create prerelease packages and publish to custom feeds

New build parameters:
- nugetpublishurl: The feed to publish too. Uses default if not specified
- nugetprerelease: Prerelease prefix.

Example: If "-nugetprerelease=dev" is used as parameter when executing
build.cmd a prerelease package will be created with a version on the format:
version + "-dev" + DateTime.UtcNow (unfortunately seconds had to be left
   out as Fake only supports an int)
For example: 1.6.4-dev14081911
Merge pull request #297 from HCanber/prereleasebuilds

Be able to create prerelease packages and publish to custom feeds

New build parameters:

- nugetpublishurl: The feed to publish too. Uses default if not specified
- nugetprerelease: Prerelease prefix.
Example: If "-nugetprerelease=dev" is used as parameter when executing
build.cmd a prerelease package will be created with a version on the format:
version + "-dev" + DateTime.UtcNow (unfortunately seconds had to be left
out as Fake only supports an int)
For example: 1.6.4-dev14081911
Run MStest on Akka.TestKit.VsTest.Tests.dll
Merge pull request #298 from HCanber/build-runs-mstest

Run MStest on Akka.TestKit.VsTest.Tests.dll
Add test that recreates bug #293

ReceiveActor never receives any messages if Base.OnPreStart isn't called from PreStart override
ReceiveActor should be initialized from ActorCell instead of doing it itself.

Fixes bug #293.
If the user did not call base.PreStart() or base.PreRestart(), Init() was never called
This introduces a new interface InitializableActor, wich has an Init method that is
called by ActorCell instead.
Merge pull request #294 from HCanber/receiveactor-293

ReceiveActor should be initialized from ActorCell
Small patch to not re-evaluate ActorPath.Elements.

Simplified awkward tennary if statement in resizer..
Merge pull request #302 from rogeralsing/dev

Small patch to not re-evaluate ActorPath.Elements.
removed Security.Claims header from FSM, which broke Mono buildper #62
Merge pull request #305 from Aaronontheweb/dev

removed Security.Claims header from FSM, which broke Mono buildper #62
FSM: Make _log obsolete  and do some cosmetic changes

- Made _log obsolete, use Log property instead.
- Renamed the generic type params to TState and TData
- Switched to use _log internally
- Fixed spelling errors
Merge pull request #310 from HCanber/fsm

FSM
- Made _log obsolete, use Log property instead.
- Renamed the generic type params to TState and TData
- Switched to use _log internally
- Fixed spelling errors