Revert "Point travis to my own RDKit fork, temporarily."
Revert "Point travis to my own RDKit fork, temporarily."

This reverts commit 99e9090e48fb9517decd08fc0dbb9a68bb417308.
RDKit have now merged my pull request to them, so their
fork has the needed fix.

pierrelb/RMG-Py,nickvandewiele/RMG-Py,enochd/RMG-Py,nyee/RMG-Py,nyee/RMG-Py,comocheng/RMG-Py,pierrelb/RMG-Py,comocheng/RMG-Py,chatelak/RMG-Py,chatelak/RMG-Py,nickvandewiele/RMG-Py,enochd/RMG-Py