[doc] Sphinx custom CSS minor adjustments
[doc] Sphinx custom CSS minor adjustments

Make custom.css like the one in python-openflow project
after kytos/python-openflow#128

macartur/kytos,cemsbr/kytos,erickvermot/kytos,renanrodrigo/kytos,kytos/kyco,kytos/kytos,erickvermot/kytos,diraol/kytos,cemsbr/kytos,cemsbr/kytos,diraol/kytos,diraol/kytos,erickvermot/kytos