add support for 1M mpeg-4 stream
change note about missing pytz module

pytz is nowadays available as deb
http://packages.debian.org/search?keywords=python-tz
http://packages.ubuntu.com/search?keywords=python-tz
Merge pull request #1 from viljoviitanen/add-1m-stream

add support for 1M mpeg-4 stream
Merge pull request #2 from viljoviitanen/fix-pytz-installation

change note about missing pytz module