Add rules for installing rsocket (#581)
Add rules for installing rsocket (#581)

* Add rules for installing rsocket

This PR makes me sad, but I'm putting it up anyway so external projects can
start installing rsocket.  Installs libReactiveSocket.a and the
yarpl/include/yarpl headers as normal.  The RSocket headers is where the fun
begins.

<clownscience>

After https://github.com/rsocket/rsocket-cpp/pull/580, they are all of the form
'#include "src/RSocketServer.h"'.  To make this resolve correctly, we actually
install the headers to /usr/local/include/src/RSocketServer.h on top of
/usr/local/include/rsocket/RSocketServer.h.  This is temporary, as I plan to
rename src/ to rsocket/ and fix the hacky install steps.

</clownscience>

* Fix not installing yarpl library, drop the dumb src/ copy.

rsocket/rsocket-cpp,phoad/rsocket-cpp,alexmalyshev/rsocket-cpp,phoad/rsocket-cpp,phoad/rsocket-cpp,rsocket/rsocket-cpp,alexmalyshev/rsocket-cpp,ReactiveSocket/reactivesocket-cpp,rsocket/rsocket-cpp,alexmalyshev/rsocket-cpp,phoad/rsocket-cpp,rsocket/rsocket-cpp,alexmalyshev/rsocket-cpp,ReactiveSocket/reactivesocket-cpp,phoad/rsocket-cpp,ReactiveSocket/reactivesocket-cpp