Update event.py

Remove ```log_persistancer```, which is currently not supported in UPSTREAM.
wrong inheritance name

bad copy & paste, sorry.
Merge pull request #25 from liorsion/patch-1

wrong inheritance name
Merge branch 'master' into lxyu-coding_style_refine

Conflicts:
	pymysqlreplication/event.py
Add MySQL Hadoop Applier
Cleanup
Fix Python 3 support
add feature to start stream from postion
allow stop event.