Replace various std::map with UNORDERED_MAP + various cleanups

This is part 2 for 5f084cd98d

Other improvements:

* Use the defined ItemGroupList when used
* make Client::checkPrivilege const
* inline some trivial functions
* Add ActiveObjectMap typedef
* Add SettingsEntries typedef

src/clientiface.h

@@ -25,10 +25,10 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "serialization.h"             // for SER_FMT_VER_INVALID
 #include "threading/mutex.h"
 #include "network/networkpacket.h"
+#include "util/cpp11_container.h"
 
 #include <list>
 #include <vector>
-#include <map>
 #include <set>
 
 class MapBlock;
@@ -502,8 +502,7 @@ protected:
 	void lock() { m_clients_mutex.lock(); }
 	void unlock() { m_clients_mutex.unlock(); }
 
-	std::map<u16, RemoteClient*>& getClientList()
-		{ return m_clients; }
+	UNORDERED_MAP<u16, RemoteClient*>& getClientList() { return m_clients; }
 
 private:
 	/* update internal player list */
@@ -513,7 +512,7 @@ private:
 	con::Connection* m_con;
 	Mutex m_clients_mutex;
 	// Connected clients (behind the con mutex)
-	std::map<u16, RemoteClient*> m_clients;
+	UNORDERED_MAP<u16, RemoteClient*> m_clients;
 	std::vector<std::string> m_clients_names; //for announcing masterserver
 
 	// Environment