Move heat keystone setup into lib/heat

Move the heat setup which currently happens in files/keystone_data.sh
to lib/heat, where we have create_heat_accounts.

Move the user, role, service and endpoint creation as that is consistent
with what other services, e.g lib/nova are doing.

Change-Id: Iaa2c822cad581d6b2b4f22f8863daf81e25f8485
Merge "Move heat keystone setup into lib/heat"