Add release section to HACKING.md

Bump version to 0.6.0

Update replicache to 0.5.2

Bump version to 0.5.0.

Bump version to 0.4.0

Whoops, version number should have been 0.3.0

0.0.6

0.0.5

Bump to 0.0.4

Roll version to 0.0.3