Blender Git Loki

Second round of hair random rotation limited to 180 degrees

This time roll back to originally discussed in the code review page approach
with simply bumping UI range for the property.

It's still not totally free from forward compatibility breaking (which is
already broken comparing to previous release) but at least it'll keep files
working inbetween of git blender versions in cases random factor was not
set above 2.0.

Differential Revision: https://developer.blender.org/D1214