Improve handling of module parameters in MOM_input

[alperaltuntas]

Currently, in MOM_input.yaml, we place parameters that don't belong to any modules under the Global block, and module parameters under respoective module blocks. For instance:

Global:
  INPUTDIR:
      ...
  TRIPOLAR_N:
      ...

KPP:
   N_SMOOTH:
      ...
   STOKES_MOST
      ...

MLE:
    USE_BODNER23:
      ...
    CR:
      ...

Given the size of this file, it's easy to make mistakes, where a parameter may inadvertently be placed under a module it doesn't belong to.

I have two improvement suggestions.

1. Rather than having module blocks, explicitlyspecify module names in parameter names. So the above entries would look like:

INPUTDIR:
    ...
TRIPOLAR_N:
    ...

KPP%N_SMOOTH:
    ...
KPP%STOKES_MOST
    ...

MLE%USE_BODNER23:
    ...
MLE%CR:
    ...

2. Turn relevant warnings into failures.

[alperaltuntas]

What do you think @mnlevy1981 ?

[mnlevy1981]

I think this is a good plan, or I could see adding an optional module key under variables:

INPUTDIR:
    ...
TRIPOLAR_N:
    ...

N_SMOOTH:
    module: KPP
    ...
STOKES_MOST
    module: KPP
    ...

USE_BODNER23:
    module: MLE
    ...
CR:
    module: MLE
    ...

I like this because it makes the top-level keys variable names (rather than a mix of variable names and module names in the current implementation, or a mix of variable names and MODULE%VARNAME in your proposal), but if the whole point of the module blocks is to allow different modules to have the same parameter name then we'll run into duplicate top-level keys.