Event Categories implementaion etc.

Please review, specially cut selections for the following event categories :

• 2lss + 0 tau
• 2lss + 1 tau
• 2los + 1 tau
• 2l + 2 tau
• 3l + 0 tau
• 3l + 1 tau
• 4l + 0 tau

and other dependent changes etc.