Add client_remove() forward and fix a bug with client not internally disconnected (#414)

* Rename client_disconnected to client_disconnecting

* Add client_disconnected as post forward

* Fix client not properly disconnected internally

Introduced in #264.
Edict is reset once SV_DropClient is called, so that second check would be always false.

* Reflect changes on the concerned plugins

* Revert renaming, let's add only client_remove as post forward

plugins/include/amxmodx.inc

@@ -178,24 +178,39 @@ forward client_authorized(id, const authid[]);
 #pragma deprecated Use client_disconnected() instead.
 forward client_disconnect(id);
 
-/**
+ /**
  * Called when a client is disconnected from the server.
  *
  * @note This will be called in some additional cases that client_disconnect doesn't cover, 
  *       most notably when a client aborts the connection process. It is guaranteed to pair 
  *       with the client_connect() forward.
- * @note By this point it is already too late to do anything that directly
- *       affects the client.
+ * @note When this fires the player entity is still valid (e.g. is_user_connected(id) will 
+ *       return true), but no networked commands will reach the client.
  *
  * @param id         Client index
- * @param drop       If true, client has been explicitly dropped by game
- * @param message    If drop is true, a disconnected message or buffer to copy a new message to
+ * @param drop       If true, the game has explicitly dropped the client
+ * @param message    If drop is true, a writable buffer containing the disconnect info message
  * @param maxlen     Maximum size of buffer
  *
  * @noreturn
  */
 forward client_disconnected(id, bool:drop, message[], maxlen);
 
+/**
+ * Called when a client entity has been removed from the server.
+ *
+ * @note This fires after the client_disconnected() forward, when the player entity has been
+ *       removed (e.g. is_user_connected(id) will return false).
+ *
+ * @param id         Client index
+ * @param drop       If true, the game has explicitly dropped the client
+ * @param message    If drop is true, contains the disconnect info message
+ *
+ * @noreturn
+ */
+forward client_remove(id, bool:drop, const message[]);
+
+
 /**
  * Called when a client attempts to execute a command.
  *