Refactor javascript implementation to be more javascripty

[chrisinajar]

• Format code (except for tests) to semistandard js coding style
  • Indentation / whitespace
  • Camel case methods and variable names
  • equals equals equals instead of equals equals
• Break out two components into 2 files, expose module.exports in sane location on each
  • previous version used two self execution functions instead of 2 files
• Test is unmodified except for including the files
  • this was previously broken out of the box anyway since bech32 was never defined
• Added note about porting to a real test case package for node instead of using raw JS and outputting the result
• Return non-zero on test fail and output a failed message at the bottom

[kurdiyaxiha]

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