Update naming to follow gatekeeper format

[garethahealy]

OPA Gatekeeper suggests a structure:

• https://github.com/open-policy-agent/gatekeeper/tree/master/library

which konstraint also uses:

• https://github.com/plexsystems/konstraint#how-template-and-constraint-naming-works

I am thinking it is a good idea to follow that.

cc @tylerauerbeck @pabrahamsson @springdo

[garethahealy]

This also means splitting the current policies out more, which is probably a good thing and something we'd of needed to do eventually.

[garethahealy]

CC @ckavili

[garethahealy]

Applied via PR: #69