Add missing return values in plugins

plugins/basevotes/voteban.sp

@@ -123,6 +123,8 @@ public int MenuHandler_Ban(Menu menu, MenuAction action, int param1, int param2)
 			DisplayVoteBanMenu(param1, target);
 		}
 	}
+
+	return 0;
 }
 
 public Action Command_Voteban(int client, int args)

plugins/basevotes/votekick.sp

@@ -121,6 +121,8 @@ public int MenuHandler_Kick(Menu menu, MenuAction action, int param1, int param2
 			DisplayVoteKickMenu(param1, target);
 		}
 	}
+
+	return 0;
 }
 
 public Action Command_Votekick(int client, int args)

plugins/basevotes/votemap.sp

@@ -132,6 +132,8 @@ public int MenuHandler_Confirm(Menu menu, MenuAction action, int param1, int par
 		
 		ResetMenu();
 	}
+
+	return 0;
 }
 
 public int MenuHandler_Map(Menu menu, MenuAction action, int param1, int param2)