version bump 0.6.5

Version bump to 0.6.4

Aside from the version number, nothing has changed between 0.6.3.1 and
0.6.4 - we're doing this as Vortex's semver module does not support 4
version components (given that we aim to automatically update the merger
this would make our lives easier)

Update README.md

version bumped to 0.6.3

Incremented to v0.6.2.

Incremented to v0.6.1.

Incremented to v0.6.0.

Incremented to v0.5.11.

Incremented to v0.5.10.

Incremented to v0.5.9.