Create custom debug & release profiles for the crate

[CPerezz]

By customizing the debug and release profiles we can get ridd of a ton of #cfg[(test)] flags as we can make debug_assert be triggered inside of debug profile while in reality we compile with release settings (for performance such that tests don't take forever).

This should make much easier writting assertions and checks which will be restricted to testing runs only (as testing will be done with debug profile now).