[CGMZ] Musical Battles - Version Alpha R3

Hi all, today this plugin was updated to version AlphaR3!
This version adds similar features for the BGS too. You can set a BGS variable which will change values depending on the current BGS in battle.
You can also control the BGS during battle the same way you do the BGM currently, such as by making skills or items that change the BGS. A new type parameter has been added, which if you want to control BGS needs to be set to either BGS or Both. This is how the plugin determines what music to modify from the skill or item cast.
- Added similar options for BGS in battle