Update travis configuration
Update travis configuration

Use new infrastructure, supposed to be faster!

hainm/pythran,pombredanne/pythran,serge-sans-paille/pythran,pbrunet/pythran,hainm/pythran,pbrunet/pythran,pombredanne/pythran,serge-sans-paille/pythran,pombredanne/pythran,hainm/pythran,pbrunet/pythran