Merging of enrichment model and client back into this repo and bump of version 0.8.0 to align with IQuery services

• To be consistent with other IQuery services, version bumped up to 0.8.0

• Bumped jetty version to 9.4.45.v20220203

• Bumped jackson-databind to 2.9.10.8

• Migrated client and model objects from https://github.com/cytoscape/ndex-enrichment-rest-client
  and https://github.com/cytoscape/ndex-enrichment-rest-model back into this code base and
  removed the dependencies

• Added new configuration option select.hit.genes which if true selects the hit
  genes. By default this is false

• If geneAnnotationServices is set in query then this service will annotate
  nodes in networks with mutation frequencies

• Fixed bug where calling delete endpoint was NOT removing the entry from the
  cache causing inconsistencies on the get endpoints

• Status endpoint now reports number of elements in cache

Jetty update

• Updated Jetty to 9.4.32.v20200930 due to bugs in previous version that
  caused service to become unresponsive