Merge pull request #403 from Collaborne/typo-start

Fix a typo in an error message
Upgrade embedded mongo and get rid of a file we had to fork to workaround a bug in the old version
IDownloader is now a part of embedded Mongo so we no longer need our own version
Don't need our own ArtifactStore anymore either now that the upstream one works
Guidlines for using the issue tracker
Update the mongo-java-driver to 2.13.0-rc0

This release contains a bunch of improvements and bug fixes, in particular:
* [JAVA-1472]: #equals()/#hashCode() for MongoClientURI
* [JAVA-1519]: DBCursor finalizer no longer holds on to the query results
* [JAVA-591] : Potential OOM with long-running tailable cursors
Disable tracking of the batch sizes received by the cursor

Relates-to: https://jira.mongodb.org/browse/JAVA-591
Merge branch 'master' into master-collaborne
Merge branch 'driver-2.13.0-rc0' into master-collaborne