We expect the server to exit when its communication pipes are closed.
Close them and wait for the server to exit. If supported by the current
version of python, kill the server if it does not exit after a few
seconds.
Do some basic unit tests for "codemodel", "cmakeInputs" and "cache"
commands of the cmake server.
This just calls the commands right now and makes sure the server
thinks it can reply to the request. The data itself is currently not
validated.
Add "globalSettings" command that returns:
* Return capability information
* Return currently used generator/extra generator
* Return a range of flags for debug/trace/etc.
