[DISCUSS] Update BYLAWS.md for clarification of code-change policy

[Kyle Nusbaum]

This is a minor change to the wording of the bylaws, sparked by the 
conversation here: https://github.com/apache/storm/pull/507
The only change is to remove the statement "The code can be committed after the 
first +1" from the code-change actions, which can be interpreted as 
contradictory to the minimum time requirements for a code change. 
A pull request for this change his here: 
https://github.com/apache/storm/pull/511
  -- Kyle