Improved Class Bonus/Penalty and Battle Calculation

An improved plugin file, consisting of a combined form of SRPG Studio Official Plugin's 'custom-class.js' and CrazyLi825's 'Jugdral Hit and Critical Battle Formula'. Great for when you want to alter battle calculations for your game, and allows you to apply bonuses/penalies to your classes, namely Hit, Avoid, Critical, Crtical Avoid/Dodge, and Agility/Attack Speed.