Wrap `Segment`

[caseykneale]

Still need to wrap line segment commands. This would be nice for displaying Graph's(as in LightGraphs not plot graphs) and things.

I might take a stab at this

[caseykneale]

Took a quick stab at this, try and understand my skills in Julia are so-so, and JS are nonexistant. Feel free to rip this PR apart and make it better, at the end of the day I just want segments to exist :).
#7