Bump the version to v0.5.1 for release.
Bump the version to v0.5.1 for release.

deployable/fakefs,defunkt/fakefs,anthonyryan1/fakefs,vhl/fakefs,fakefs/fakefs,dekz/fakefs,bquorning/fakefs,onehub/fakefs,marxarelli/fakefs,1234-/fakefs,pivotal-cf-experimental/fakefs