SCRIPTS: Fix Curing Waltz III to Be Usable by /DNC

According to FFXIclopedia, Curing Waltz III is usable by /DNC, but the amount of HP healed is calculated slightly differently. The current script healed 0 hp is dancer was not your main job.

Formula (for DNC): Amount Healed = floor(((Target's VIT+Caster's CHR)*0.750) + 270,1)

Formula (for /DNC): Amount Healed = floor(((Target's VIT+Caster's CHR)*0.375) + 270,1)

http://wiki.ffxiclopedia.org/wiki/Curing_Waltz_III
Merge pull request #191 from starlightknight/curing-waltz-iii-sub-fix

SCRIPTS: Fix Curing Waltz III to Be Usable by /DNC