bundles: turn nbchanges int into a bytestr using pycompat.bytestr
Fixes some python 3 failures.
exchange: hit opargs with pycompat.strkwargs before **-ing it
Fixes Python 3 problems.
revlog: update signature of dummy addgroup() in bundlerepo and unionrepo
Per
c8b6ed51386b,
2f5c45fe3a3b and
00e3f909907f.
py3: use 'surrogatepass' error handler to process U+DCxx transparently
It's disallowed by default on Python 3.
https://docs.python.org/3/library/codecs.html#error-handlers