Split layer packages by Spark and Collections classes

[echeipesh]

Connects: https://github.com/locationtech/geotrellis/issues/2916

This issue is to split out backend-specific packages in twain: one for spark and one for collections API

• [x] Diagram the split and agree on package naming convention (2 point)
• [x] Split geotrellis-geomesa (1 points)
• [x] Split geotrellis-geowave (1 points)
• [ ] Split geotrellis-pipeline(1 points)
• [ ] Split geotrellis-s3 (2 points)
• [x] Split geotrellis-hbase (2 points)
• [x] Split geotrellis-accumulo (2 points)
• [x] Split geotrellis-cassandra(2 points)

The tests should remain in the spark version of the packages because currently their implementation is very much coupled to reading and writing layers using spark. Putting in the effort to split the tests doesn't seem worth it right now.

[pomadchin]

Just a note about fixing the tests: all scripts from .locationtech, .travis and scripts dirs should be fixed, since we have more projects now and all the names were changed.

[echeipesh]

Resolved by https://github.com/locationtech/geotrellis/pull/2972