Use the https not git@ protocol to get the RMG-database in .travis.yml
Use the https not git@ protocol to get the RMG-database in .travis.yml

The builds got this far then stopped for 10 minutes and were killed:
$ git clone git@github.com:GreenGroup/RMG-database.git
Cloning into 'RMG-database'...
The authenticity of host 'github.com (192.30.252.128)' can't be established.
RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
Are you sure you want to continue connecting (yes/no)?

Hopefully the https version can continue without the RSA fingerprint check...

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