Several fixes for minor issues

Addressing several "small" issues with the game in a single merge request for convenience, the fixes are as follows:

Clean up vote list checking code to not check empty lists/votes, closes #2751 (closed)
Remove spawned monsters when the map is reset, closes #2749 (closed)
Add an option to allow monsters to drop their items in CTS (off by default), fix the error that occurs when this setting is off, closes #2734 (closed)
Remove the "corrupted" skin from the Mage as the effect of it is very unclear, closes #2704 (closed)
Disable warnings related to projectiles touching eachother that serve no purpose other than to spam the log, closes #2360 (closed)
Thrown flag will start its capture timer when it first touches the ground rather than when it was thrown, to allow pushing it off before it captures if thrown from a distance, closes #2135 (closed)
Flag dropped capture delay (g_ctf_dropped_capture_delay) is adjusted to 1 second (down from 1.5) to accommodate this change