Remove CISM_USE_GREENLAND and CISM_USE_ANTARCTICA

In #87 I am changing CISM_USE_GREENLAND and CISM_USE_ANTARCTICA to GLC_USE_GREENLAND and GLC_USE_ANTARCTICA for backwards compatibility until https://github.com/ESCOMP/CTSM/pull/2449 comes in. Once https://github.com/ESCOMP/CTSM/pull/2449 is in place, we should remove these deprecated variables.