#87 Module documentation before refactoring
#87 Moved some extension support types to the `extension-api`module
#87 Cutting the link between `service` and `extension-general`
#87 #88 Removing LDAP integration tests (not enabled, and failing locally)
#87 Migration action moved to `service` module
#87 Cutting the link between `repository-impl` and `security`
#87 Cutting the link between `extension-support` and `security`
#87 Removing the `security` module
#87 Removing the `ref` module
#87 Added colours to the module graph to document extension boundaries
#87 Hard-coding of the crypto key name since we have to maintain backward compatibility after class move