Fix d3q27 pf corner bug

[TravisMitchell]

A few changes and updates to be pushed:

• minor updates in flow d3q27 and d3q27_cumulants to make perm calculations easier
• minor updates in d2q9_pf_velocity to allow for droplet on solid in shear flow test case
• clean up of d3q27_pf_velocity and attempted fix of corner bug created with the q15 lattice for the allen-cahn equation
• also added required outputs to get densities for machine learning applications.
• grabbed from Bryce's branch the addition of BOUNDARY field for catalyst operations
• added d3q27_n1 values to globals from Dmytro's branch for alternate contact angle implementation

[TravisMitchell]

will resolve these conflicts, a bit later before talking to @llaniewski about merging.

[llaniewski]

@TravisMitchell how this is going?

[TravisMitchell]

@llaniewski I just resolved the conflicts and it should be okay to merge for now. It has some improvements on the current d3q27_pf_velocity model that is in develop, and the test gave back equal results in the benchmark repo that I have for the model.