Changes

Fixed some oversights for the bv_efold commits and increased string length for tuning field names for invrs_tau variables - CLUBB ticket #1069 (#1106)

This commit is NOT bit changing
- Removed remaining mentions of brunt_vaisala_freq_sqd_plus
- Added assignment for invrs_tau_wp3_zm in Lscale mode in advance_clubb_core
- Increased length of string variables hoc_v, les_v, and t_variables in src/error.F90 to accomodate tuning for invrs_tau fields

BIT_CHANGING! brunt_vaisala_freq_sqd_mixed now replaces brunt_vaisala_freq_sqd for later calculations - CLUBB ticket #1102

Changes in src/CLUBB_core/mixing_length.F90:
- brunt_vaisala_freq_sqd_mixed is now used to calculate brunt_vaisala_freq_sqd_smth and brunt_vaisala_freq_sqd_clipped instead of brunt_vaisala_freq_sqd
- Removed 0.1 factor for bkgnd term in calculation of invrs_tau_xp2_zm
- Commented out clipping of invrs_tau_xp2_zm to 0.003 and lower out of cloud