Port to Javascript & infinite loop

[Fil]

Hello,

I ported @yongyanghz 's C implementation to Javascript (https://github.com/Fil/lap-jv) and we were discussing the infinite loop problem (https://github.com/yongyanghz/LAPJV-algorithm-c/issues/2), for which I introduced an epsilon in the code (https://github.com/Fil/lap-jv/blob/master/lap.js#L42).

This epsilon tolerance solves the issue for my test cases but it would be good if we had a solid (and common) approach.