Update method sigs to pass meta through to .people_update() and .track(); apply meta vars appropriately to top level of dict before serializing to JSON.
Test that meta vals are being sent
Change test method order for tidiness
Test for meta in events
Hurrah for tests -- was updating wrong dict!
Merge branch 'master' of https://github.com/sbnoemi/mixpanel-python into 2.0.2rc
Tests with default ip=0