Additional documentation for DEPHY

[hertneky]

• Originally addressed in Converting to DEPHY format #518, add documentation for the DEPHY converter script.
• Document a disclaimer for using NSST scheme for ocean points in SCM. From Grant: For oceanic field campaign cases, I think that we should be using either suites with the sfc_ocean scheme rather than NSST unless we have the additional required input like depth of the thermocline, etc. OR use prescribed surface fluxes. I'm not at all confident in how the NSST scheme works. It appears that if we give it an initial SST, it produces reasonable surface fluxes, but it also produces its own SST that diverges slightly from the prescribed value. It is only using the prescribed SST for the first time step. It must be using some kind of default values for the mixed layer above the thermocline, but I'm not sure if that's really what we want?