Getting Started walkthrough for a sample app (including RM)

[JeroMiya]

Some users are reading the OSVR-Docs readme and thinking that they need to build all of OSVR-Core just to get a sample application running. There doesn't appear to be a getting started document for the purpose of just getting a client application built with the binaries from the OSVR Runtime installer (or the snapshots).

This walkthrough should tell them how to:

1. Install the SDK (link to the corresponding OSVR-Docs page).
   • Make sure to mention the added step to run the "register sdk" script.
2. Where to get the boilerplate standalone CMake project.
3. Maybe some bare minimum notes on how to get a project configured/built or a link to CMake documentation, etc...