Add job to collect IDs in object position with their subject as key
Consistent naming for integration and unit tests
WIP: add failing integration test for JSON-LD conversion (see #108)
WIP: basic approach for collecting triples with distributed cache

This breaks some unit tests which are commented out and it doesn't
yield the desired JSON-LD yet (it seems like blank nodes are not
handled correctly in Jena or jsonld-jena).

Also, this would not scale as implemented here - we would at least
need to use map files for the cached subjects to avoid keeping them
in RAM on every node.
Add unit test for JSON-LD conversion w/ blank nodes, fix job issue

This is still work in progress at this point. The JSON-LD output
for input with blank nodes has changed significantly and is not
compatible with the rest of the system.
Fix issue with removed unit tests and add them back
Replace in-memory subjects map with on-disk map file to save memory
Add test case for resolving objects used by multiple subjects
Update scripts and jobs for distributed cache file handling
Write map file during job setup, store as zip in distributed cache
Skip invalid triples and log details
Tweak new resolution logic and job setup for larger inputs

Only collect details on specified properties to keep the map file
stored in the distributed cache small. Increase the reducer heap
size and some other minor tweaks to save memory.
Move zip file creation from conversion to collection job
Pass prefix of subjects to be processed to the jobs
Improve assertions in job integration tests
Add time stamps to index names in scripts

Combined with Elasticsearch index aliases, this should fix #94:
when reindexing, a new index is created. When done, we can update
the aliases used by the API to point to the new indexes, and
finally delete the old indexes.
Some performance tweaks & cleanup in collection and conversion jobs

Only look up subjects in the map file for triples with specified
predicates. Some minor tweaks and cleanup (pull things up from map
functions into mapper setup to do them only once).
Remove old code and dependencies, update tests

Delete the old resolution job replaced by `CollectSubjects`, adapt
its unit tests, and do some cleanup in the new job's mapper. This
renders the JFresnel dependency and FSL paths in resolve.properties
obsolete, so remove these too.

While at it, remove the old main to run the jobs locally (replaced
by the integration tests) and the even older experimental SPARQL
stuff not used anywhere in the project.
Merge pull request #116 from fsteeg/issue-108-hadoop

Collect triples with different subjects for JSON-LD conversion