feat(running-coreos): add channel instructions
fix(ec2,gce,rax): include additional tabs for switching channels
fix(bare-metal): improve channel selection info
fix(running-coreos): remove references to master channel
fix(ec2): use correct name on beta CF stack
feat(gce): use public gce image path
Merge pull request #186 from robszumski/multi-channel

feat(running-coreos): add channel instructions