Reimplemented the push/pop entity methods in RoomManager

Some accessors in Entity had to be made const, as they were being called
from lambdas with const parameters.

server/server_character_methods.cpp

@@ -45,6 +45,9 @@ void ServerApplication::HandleCharacterCreate(CharacterPacket* const argPacket)
 		return;
 	}
 
+	//push to the rooms
+	roomMgr.PushEntity(characterMgr.Get(characterIndex));
+
 	//pump this character to all clients
 	CharacterPacket newPacket;
 	CopyCharacterToPacket(&newPacket, characterIndex);
@@ -86,6 +89,9 @@ void ServerApplication::HandleCharacterDelete(CharacterPacket* const argPacket)
 		return;
 	}
 
+	//pop from the rooms
+	roomMgr.PopEntity(characterMgr.Get(characterIndex));
+
 	//delete the character
 	characterMgr.Delete(characterIndex);
 
@@ -119,6 +125,9 @@ void ServerApplication::HandleCharacterLoad(CharacterPacket* const argPacket) {
 		return;
 	}
 
+	//push to the rooms
+	roomMgr.PushEntity(characterMgr.Get(characterIndex));
+
 	//pump this character to all clients
 	CharacterPacket newPacket;
 	CopyCharacterToPacket(&newPacket, characterIndex);
@@ -149,6 +158,9 @@ void ServerApplication::HandleCharacterUnload(CharacterPacket* const argPacket)
 		return;
 	}
 
+	//pop from the rooms
+	roomMgr.PopEntity(characterData);
+
 	//unload the character
 	characterMgr.Unload(argPacket->characterIndex);
 
@@ -190,11 +202,17 @@ void ServerApplication::HandleCharacterSetRoom(CharacterPacket* const argPacket)
 		return;
 	}
 
+	//pop from the old room
+	roomMgr.PopEntity(characterData);
+
 	//set the character's room, zero it's origin, zero it's motion
 	characterData->SetRoomIndex(argPacket->roomIndex);
 	characterData->SetOrigin({0, 0});
 	characterData->SetMotion({0, 0});
 
+	//push to the new room
+	roomMgr.PushEntity(characterData);
+
 	//update the clients
 	CharacterPacket newPacket;
 	CopyCharacterToPacket(&newPacket, argPacket->characterIndex);