Remove 'Class' suffix from generated TypeScript types

[pcornish]

Comment from @Joe-Edwards-GDS on #106

It would be nice if we could get rid of the Class suffixes!

The generated TypeScript types have the Class suffix mirroring the naming in the vocab site. This suffix isn't technically required in TypeScript and Java. The Java types strip off the suffix. We should look for an equivalent mechanism in TypeScript.

[chris-dco]

@pcornish Do you still require this or are you happy for me to close it as a stale ticket?