Resolve "CA uses LMS start values" and same for FT

Added cvars for CA and FT start items in balance files. Changed the CA and FT so that they check their own start values. Also undocumented the lines in sv_freezetag.qc which stop starting health and armor values from being changed. g_ft_start_health is 100 and g_ft_start_armor 0 so there's no noticeable effect without editing cvars.

Closes #2259 (closed)