Added cgfx and ctpk support for Awakening texture files + refactoring

[SinsofSloth]

• Refactored texture decoding functions from bch into texture_decoder module for cgfx and ctpk modules to access
  • ETC1 module included in texture_decoder module
• Changed arc module to return arc object instead of texture object to expose is_awakening flag
  • Added awakening support to open_arc function in hack_filesystem module
• Refactored bch
  • Implementations for structs to follow logic of original source code
• Tested cgfx and ctpk, and they work. bch and arc modules both still work after refactoring.

[thane98]

This looks awesome!

Paragon's currently undergoing a rewrite, so this will need some adjustments to to integrate with the new filesystem implementation, but I can handle that piece. I will look into using this from the Python code as well.