Need to revise PFragment initialization

[codeanticode]

Android Studio warns about the PFragment(PApplet sketch) constructor:

For one it seems to be ok, but at some point we should follow the "strong" advice from Google. Some useful links to look at:

https://developer.android.com/reference/android/app/Fragment.html#Fragment() https://stackoverflow.com/questions/4249897/how-to-send-objects-through-bundle http://blog.petrnohejl.cz/handling-bundles-in-activities-and-fragments