Added and wrote splitterand L1 pressure transforms
Added basic test code that just launches for now. Will add more int testing later
updated documentation on the python files
updated comments
removing an output field in pres_L1
needed to another change. removing a duplicate equalling
one more cleaner code change
Merge pull request #538 from swarbhanu/pressure_transforms_splitter_and_another

Adds two pressure transforms- 1. splitter and 2. L1 transform