Add "globalSettings" command that returns:
* Return capability information
* Return currently used generator/extra generator
* Return a range of flags for debug/trace/etc.
Use it to split pipe and stdin/out handling out of cmServer itself.
The server will shut down when it looses its connection to the client.
This has the nice property that a crashing client will cause the server
to terminate as the OS will close the connection on behave of the client.
Allow for experimental cmProtocolVersions, which will only ever get
listed if the server was started with the (undocumented)
"--experimental" flag.
Mark current protocol version 1.0 as experimental.
Tobias Hunger