Fix some memory leaks and code style issues

Maximum line length is 95 characters.
Some members' name are changed.
Struct initialisations use brace syntax; eliminating the usage of the memset function.
Iterations use for-each-loop instead of while-loop+iterator.
char * -> std::string
button_info * -> std::shared_ptr<button_info>

src/client/inputhandler.cpp

@@ -104,7 +104,7 @@ bool MyEventReceiver::OnEvent(const SEvent &event)
 	if (isMenuActive()) {
 #ifdef HAVE_TOUCHSCREENGUI
 		if (m_touchscreengui) {
-			m_touchscreengui->Toggle(false);
+			m_touchscreengui->setVisible(false);
 		}
 #endif
 		return g_menumgr.preprocessEvent(event);