Exotica Trigger Validation package, modified and shouldn't crash anymore

Hi

I have revamped the package, and I think it should be safe now.
Essentially, a std::vector<MatchStruct> (a custom class) was going wild, with its memory addresses jumping around. While I couldn't solve that problem, I moved the implementation to std::vector<LeafCandidate> and it's working now.

Compiles cleanly in CMSSW_7_1_X_2014-03-31-0200
Runs successfully in workflows 12, 24, 36 and 1325

![screen shot 2014-04-03 at 00 33 23](https://cloud.githubusercontent.com/assets/4937855/2598136/fcac7554-babf-11e3-8801-5c183f847e83.png)
![screen shot 2014-04-02 at 23 36 42](https://cloud.githubusercontent.com/assets/4937855/2598137/fcb1e94e-babf-11e3-953e-114cf5002402.png)
![Uploading Screen Shot 2014-04-02 at 23.09.42.png . . .]()
![Uploading Screen Shot 2014-04-02 at 23.57.41.png . . .]()