create qauld-ctl to control qauld

[MathJud]

The qaul daemon qauld runs headless in the background. Create a second binary qauld-ctl To control it. For this you also need to setup a communication channel between qauld and qauld-ctl over which you can control qauld via the protobuf RPC.

• Create a local communication channel for qauld which is only locally accessible (e.g. a unix socket)
• Create a new qauld-ctl CLI binary that connects to qauld
• Send protobuf messages from qauld-ctl to qauld and display the results in qauld-ctl
  • For how to use the protobuf RPC to control libqaul, check qaul-cli