Fix NickServ ACC command short descrption

All command short descriptions returned by `/msg NickServ HELP COMMANDS` end with a period except for the ACC command. This pull request simply fixes a grammatical inconsistency in the project.
protocol/unreal: fix checking of +f syntax

check_flood would immediately return false regardless of action char
validity, and check_flood_old was expecting a ':' but actually checked
for '*'.