[analyzer] Include bug column numbers in HTML output (in a comment).

This has no effect on user-visible output, but can be used by post-processing
tools that work with the generated HTML, rather than using CmpRuns.py's
interface to work with plists.

Patch by György Orbán!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@194763 91177308-0d34-0410-b5e6-96231b3b80d8