Convert role templates to consume roles_data map

Convert role templates to consume roles_data map

Currently we only consume the name with a special-case
for the disable constraints boolean, but it will be more
flexible if we consume the whole roles_data mapping for
each role, so that e.g composable networks and other
per-role customizations can be expressed in these
templates

Partially-Implements: blueprint composable-networks
Depends-On: Id1249b78b3dd87e91d572ffa31b7a541f3cde2c7
Change-Id: I355534ec456479944f66106e957404a660d8f2d2