Move the "creating an issue" section from bugpoint.rst to "reporting bugs" in `contributing.rst`.
Fix link to `CONTRIBUTING.md`.
Update `CONTRIBUTING.md` to refer to the bugpoint guide instead of the stack overflow guide.
Drop the parts that are being dropped.
Move the things that are being moved.
Also move the verilog stuff out of README and into the docs.
GettingStarted is less cut and dry, so hold off on that one.
