I just saw this project and it seem amazingly useful, but unfortunately I'm mainly working with CDT right now. I saw an interview where you've been saying something about "bring Code Recommenders to the C-family" and I would love to know what's going on with that.
I also would love to help, even though I have zero experience with plugins developing.
Support for CDT is not in sight yet, sorry.
Adding support for C in general would be a huge effort that probably takes more than 10 man months. In particular the static analysis is something quite tricky. As much as I appreciate your offering, but I think adding support for C on a voluntary basis is too large without sponsored development.