Committer's note: I rewrote this from the original PR
at #23 for three reasons:
1. The preceeding code usually case folded $current,
   but may not depending on the value of $all and $current.
   This was likely the source of the original issue being addressed.
   By using strcasecmp(), the comparison no longer cares about case.
2. While $bug_types is *probably* safe to output unescaped,
   it makes sense to be defensive and add some output protection.
3. Readability

-Sara