Added UpdateDefendersObjective() function
- makes it easier to change objective and removes some redundancy
- also fixes some old issues with _onflag and _oncarrier code
#58
DEFENDERS_OBJECTIVE_ONCARRIER plus code
Changed DEFENDERS_OBJECTIVE_ONFLAG and
DEFENDERS_OBJECTIVE_ONCARRIER to false
Modified/Added if statements to keep old code and still see only
the cap and to include the UpdateTeamObjectiveIcon() for D so
that it only gets called when necessary