Added Plugin Scripts.

After wasting about 2 hours on trying to import the history of these two script files from another repository (and learning stuff about some git commands) I am just adding these files as new.

The output json looks like this: https://github.com/dufferzafar/picard-plugins/blob/master/Plugins.json

To test the scripts, you'll need a folder containing picard plugin files. I have a setup here: https://github.com/dufferzafar/picard-plugins
Yes, it'd be used in the output too, unless there are reasons to store it as a list (and there might be, though I can't think of any at the moment).