Compile Instructions

[TonyRippy]

Hello, and thank you for all your work on this library!

As part of a PR I was working on, I was trying to figure out how to regenerate the fraction.min.js file. The project README.md file mentions that you use google-closure-compiler with advanced optimizations, but I was unable to find the right combination of compiler flags to get this working. If it helps, here is what I tried: TonyRippy/Fraction.js#e3779a2

Would it be possible to publish instructions that document what compiler flags and other settings you use to build the project?