setup: normalize casing of dependencies and formatting of constraints

The package name casing might seem random, but it is more correct than our own random casing.

These changes mainly come from:
pip freeze | sed -n '/==/s/==.*//gp' | while read a; do sed -i "s/$a/$a/i" setup.py dev_requirements.txt ; done
sed -i -e 's/>=/ >= /' -e 's/ >=/ >=/' -e 's/>= />= /g' -e 's/,</, </' -e 's/</< /' -e 's/< /< /g' -e 's/< =/<= /g' setup.py dev_requirements.txt