Add merge_fluid method to GenericNetwork.
* The adds the fluid conditions to the netowrk.pore_properties (appended with the fluid name)
* The idea was to make a big dictionary for printing to VTK and sending to Paraview
More Fluids stuff
* moved contact angle to fluids from physics
* add some utitlity functions to GenericFluid
* got the occupancy checking working for OP, tho still stored under physics and not with algorithm
Got Algorithms working with Fluids (as far as I can tell)
* I sorted out all the argument passing
* IMPORTANTLY, I started moving all Physics calls out of the algorithm setups and onto main script.  We expect the user to customize these methods, but burying them in the subclassed run methods undermined that.  Not the user is expected to call all the necessary physics first.
Updating Visualization for Fluids: fail
* VTK file outputs fine, but Paraview crashes when I load it.  Could be corrupt file, or bad paraview install.
Introduced defending fluid to OP arguments
* This is not actually used, but it will force the user to define the defending phase which is essential for interpreting the results
* The setup runs the set_pairs method to link the two fluids.  This step needs major checks built in to prevent any mixups and overwrites of pairings.
Minor cleanups
Added defending_fluid to IP too
* as well as set_pairs
ALL FIXED!!
* The JTG3 script runs numerous things without breaking
* Let's keep it that way