Update V1.2.1 - Bugfixes

Hi everyone, new update fixing some bugs caught by myself and others:

• POSY now takes RESET correctly.
• POS's endpos value now takes RESET correctly.
• SIZE and LINE's syntax is now written properly in the guide.
• RECT can now also take RAND in the x, y, width, and height values.
• Music will now load correctly if VT loads a track that hasn't been played before.
• Transparent videos have much better support, and now display properly when placed on a layer with other content there before.