IMPORTANT: Updated ROMS standard input files and build script

[arango]

• This update includes the changes discussed in ​src:ticket:945 to ROMS input scripts (roms_*.in), build scripts (build_roms.* and cbuild_roms.*), and metadata file varinfo.yaml.

• The makefile was updated to rename of macro SCRATCH_DIR to BUILD_DIR. Code was added for backward compatibility with old make configuration files (Compilers/*.mk):

  BUILD_DIR ?= Build_roms
  
  #  Backward compatability with old build scripts and make configuration
  #  files (*.mk). The BUILD_DIR macro is preferred.
  
  ifdef SCRATCH_DIR
    BUILD_DIR := $(SCRATCH_DIR)
  else
    SCRATCH_DIR := $(BUILD_DIR)
  endif
  

• Similarly, the make configuration in Compilers/*.mk were updated to rename macro SCRATCH_DIR to BUILD_DIR.

• Corrected spelling in the source code documentation. We need to use Charnock instead. However, the roughness variable is still charnok_alpha, and the CPP option is still CHARNOK.

• Added the logical switch for implicit omega in read_phypar.F:

  # ifdef OMEGA_IMPLICIT
              IF (Hout(idOvil,ng)) WRITE (out,170) Hout(idOvil,ng),       &
       &         'Hout(idOvil)',                                          &
       &         'Write out omega implicit vertical velocity.'
  # endif