cs_entrymsg: Check for the correct override privilege.

Make some more commands check if Read-Only mode is active.
cs_flags: Show a meaningful message when a user is not found on the access list.
os_set: Add missing capabilities to the readonly help output.
OperServ: Add logging to certain commands.
NickServ: Undo logging for listings.

modules/commands/cs_list.cpp

@@ -170,6 +170,12 @@ class CommandCSSetPrivate : public Command
 
 	void Execute(CommandSource &source, const std::vector<Anope::string> &params) anope_override
 	{
+		if (Anope::ReadOnly)
+		{
+			source.Reply(READ_ONLY_MODE);
+			return;
+		}
+
 		ChannelInfo *ci = ChannelInfo::Find(params[0]);
 		if (ci == NULL)
 		{