Add PC_TOPIC flag to prepare_command() for topic-change commands.

Clean up e_topic(), splitting out untopic() and using prepare_command()
to check for ops.


git-svn-id: svn://svn.code.sf.net/p/bitchx/code/trunk@136 13b04d17-f746-0410-82c6-800466cd88b0

include/misc.h

@@ -36,6 +36,7 @@ enum color_attributes {
 };
 
 #define DONT_CARE 3	
+#define PC_TOPIC 2
 #define NEED_OP 1
 #define NO_OP 0