port ereviewboard to mylyn 3.10

A quick and dirty fix to port ereviewboard to mylyn 3.10.
1. All junit plugin tests are green
2. Try on reviewboard 1.7.20 + svn
What works
  create/publish review request
  create top/bottom review
  create inline review
  ship it
What not works
  attachment
  ... ?
 
  
3. Including a fix for discarding review draft