Added layer between validation and projects API layer. New service for
pagination of projects. This uses manually incrementing pages rather
than using link headers. This is not easily done within the RESTeasy API
builder paradigm, and will be taken as technical debt to fix. Added
separate cache layer to solve issue with long load times and always
available data with Loading rather than on demand cache.

Signed-off-by: Martin Lowe <martin.lowe@eclipse-foundation.org>