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
I tried using the `imp.load_source` function but that sadly doesn't work as the plugins themselves rely on [other Picard modules](https://github.com/dufferzafar/picard-plugins/blob/master/Plugins/addrelease/addrelease.py#L12). So loading them raises an `ImportError`, though I am not sure whether I'm doing this right or not.