Added AppVeyor support

When building on AppVeyor

- Fixes the repo as AppVeyor does a shallow clone of just the branch that's changed.
- AppVeyor uses a Rest API to change the build version.
- Makes the build version "x.x.x (Build ##)" because each AppVeyor build number must be unique, so appending the build increment achieves that. Only the AppVeyor build number is affected.