* delete unused locals
* add some code that has been forgotten when copying and overriding the vanilla renderHealth method
* create dedicated class HealthBarRenderer extending Gui to stop copy-pasting certain vanilla methods
* fix renegeration hearts moving when the game is paused
* only bind tinkers hearts textures if it's actually going to draw tinkers' hearts
* stop drawing vanilla hearts when they are hidden by tinkers' heart being drawn on top
* fix tinker's half heart not moving with regeneration
* fix drawing all tinkers' hearts on top of each others, and now only draw the top most hearts
* add comment to help with debugging
charagarlnad