On laptops with integrated+discrete adapters, adapter 0 may not
support D3D12, so a default create device call will fail. Adapters
other than the 0th one need to be specified explicitly.
* Instead of only doing a very lightweight check to see if the API is available
up-front, we now share the API initialisation among all API tests far enough
to determine availability of extensions, features, etc. Then we can precisely
determine which tests are available and which aren't before running.
* Where available - on Win8+ basically. On win7 the video doesn't play (but most
of the demo also doesn't work, so that's not much change).
* Added a short 10kb clip from Caminandes (http://www.caminandes.com/sharing)
* Built entirely independently of the main renderdoc build (for now).
* Contains python scripts & framework for running tests on a renderdoc build,
which will be run nightly.
