Added support for project:issue-number queries

Added support for project specific issues (Chromium is the still default when the project name is omitted). b:v8:989, b:skia:822 and so on.
This is not optimized at all (it is called several times per query - creating an object every time - instead of being cached and re-used), but so was the previous code (though it was much simpler).
Ah right. It says at the bottom:

"We can’t automatically merge this pull request.
Use the command line to resolve conflicts before continuing."

Will you have access to a CLI? Otherwise I can see if it's possible for me to do the rebasing.