Changes

There were furhter issues found with the k_lh_start code.

The code would find that sometimes, the maximum location of rcm
in cloud would occur at the ghost level, k = 1, and set that level
as k_lh_start for SILHS. This is undesirable for two reasons:
1) k_lh_start should be set around a legimate, "within domain" grid
level; and
2) Setting k_lh_start to 1 is unachievable for the ghostless branch
of the model, making a match between the master and clubb_ghost_exorcism
branhes unattainable.

The issue is corrected here by allowing the maxloc function to only
search over "in-domain levels" for maximum cloud. The results are
BIT_CHANGING.

Ri_zm calc (Part 3) - Moving calculations for Ri_zm out of diagnose_Lscale_from_taus (#1157)

CLUBB tocket #1145
BIT_CHANGING for lscale since Ri_zm was not calculated before.

1. mixing_length.F90:
- Removed unused input variables from diagnose_Lscale_from_taus: um, vm, exner, p_in_Pa, rtm, thlm, thvm, rcm, saturation_formula, l_brunt_vaisala_freq_moist, l_use_thvm_in_bv_freq, l_modify_limiters_for_cnvg_test; added ddzt_umvm_sqd as input; changed Ri_zm from out to in
- Removed unused brunt_vaisala_freq_sqd variables from diagnose_Lscale_from_tau
- Removed calculations for Ri_zm and ddzt_umvm_sqd
- Fixed some line length issues

2. advance_helper_module.F90
- Removed unused input variables and imports
- Fixed some line length issues

3. advance_clubb_core_module.F90
- Added calculations for ddzt_umvm_sqd and Ri_zm
- Adjusted subroutine calls
- Fixed some line length issues