Added requirements file and updated instalation docs. Fixes #216

Currently translated at 100.0% (780 of 780)

Currently translated at 100.0% (780 of 780)

Added install instructions for OSX

Currently translated at 94.2% (735 of 780)

Currently translated at 92.9% (725 of 780)

Currently translated at 10.3% (80 of 780)

This way we can skip complex evaluations if simple ones do pass.

Currently translated at 98.5% (768 of 780)

Currently translated at 9.2% (72 of 780)

Currently translated at 92.8% (724 of 780)

Currently translated at 100.0% (16 of 16)

Currently translated at 100.0% (780 of 780)

Currently translated at 100.0% (780 of 780)

Currently translated at 100.0% (780 of 780)