jsonrpc: Make jsonrpc an independent package

The json-rpc core is needed by the client and by the server.

I changed the package name to yajonrpc (yet another json-rpc) to avoid
collisions with existing jsonrpc implementations.

Change-Id: I09e5718d56e09e7f6ad36bc3b2f241c03bbaf08b
Signed-off-by: Saggi Mizrahi <smizrahi@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/11710
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>