perf: introduce more cache invalidation option in perf::tags This will help us to assert the performance of different versions in more diverse situations. We introduce helper function in the tags module in case invalidating such cache becomes different in the future.

hgweb: pass strings in WSGI environment correctly from wsgicgi According to PEP 3333, the strings in the WSGI environment must be translatable to bytes using the ISO-8859-1 codec.