Refactor package entry module

[m-mujica]

I was having some trouble following transpile's entry module code and decided to document some things, re-org some code and add a few tests.

😅

• Document the bfs module
• Document transpile.able
• Move logic to create formats graph into its own module (and test it)
• Remove some custom function in favor of built in JS functions

[matthewp]

:+1