Add "Open Hardware" technology type tag

Hi.

This ticket is related to #420 (closed)

We would like to have an "Open Hardware" tag defined to track projects related to the OpenHW Foundation.

Right now, this will only apply to the CORE-V project. However, @mthompson7k1 and @wbeaton are currently working on a new project structure. So, there will eventually be several projects in that category.

Thank you! I appreciate your support.

cc @tmashologu