Fix travis build to point at v0.3 explicitly
Fix travis build to point at v0.3 explicitly

SymbiFlow/pycapnp,SymbiFlow/pycapnp,tempbottle/pycapnp,jparyani/pycapnp,jparyani/pycapnp,jparyani/pycapnp,rcrowder/pycapnp,tempbottle/pycapnp,jparyani/pycapnp,SymbiFlow/pycapnp,SymbiFlow/pycapnp,rcrowder/pycapnp,rcrowder/pycapnp,rcrowder/pycapnp,tempbottle/pycapnp,tempbottle/pycapnp