Reorder Dockerfile for rebuild speed
Reorder Dockerfile for rebuild speed


Former-commit-id: a1805d687005c42170e056d6dbae819217fe60be
TrimBiggs/libnetwork-plugin,projectcalico/libnetwork-plugin,caseydavenport/libcalico,insequent/libcalico,djosborne/libcalico,plwhite/libcalico,robbrockbank/libcalico,tomdee/libnetwork-plugin,TrimBiggs/libcalico,TrimBiggs/libnetwork-plugin,Symmetric/libcalico,L-MA/libcalico,alexhersh/libcalico,tomdee/libcalico,projectcalico/libcalico