Fix input system ignoring mouse input

Regression from commit ecc0dca.

It turned out that the "hotkey" system is involved even when mouse clicks
are processed. Therefore my code treated pressing a mouse key as a press
only if there was a keyboard key release since the last mouse click.
The result was that mouse input seemingly didn't work at all.

Fixed by always treating mouse (and joystick) key presses as key presses
regardless of whether there have been key release events in between.

src/hotkey/command_executor.cpp

@@ -549,13 +549,15 @@ void command_executor::execute_command(const SDL_Event& event, int index)
 	}
 
 	const hotkey_command& command = hotkey::get_hotkey_command(hk->get_command());
-	bool press = (event.type == SDL_KEYDOWN ||
-		event.type == SDL_JOYBUTTONDOWN ||
-		event.type == SDL_MOUSEBUTTONDOWN ||
-		event.type == SDL_TEXTINPUT) &&
+	bool keypress = (event.type == SDL_KEYDOWN || event.type == SDL_TEXTINPUT) &&
 		!press_event_sent_;
+	bool press = keypress ||
+		(event.type == SDL_JOYBUTTONDOWN || event.type == SDL_MOUSEBUTTONDOWN);
 	if(press) {
-		LOG_HK << "sending press event\n";
+		LOG_HK << "sending press event (keypress = " <<
+			std::boolalpha << keypress << std::noboolalpha << ")\n";
+	}
+	if(keypress) {
 		press_event_sent_ = true;
 	}