Regional decomposition test fix (when nrows_blend > 0) (#194)

[JiliDong-NOAA]

• Add missing instance for hailwat

• Regional bc blend changes to extend into interior halos and overlap on corners. Still not working for u and v.

• atmosphere.F90 : add hailwat to check
  dyn_core.F90 : Fix from Jun Wang to correct sync of u,v
  fv_regional_bc.F90 : add check for nrows_blend > tile size; fix error when nrows_blend=1

• Explanatory comment added

• Removed commented code

• Clean old code

Description

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Fixes # (issue)

How Has This Been Tested?

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