Version 1.0-RC2

Fixing gradle versions plugin
Updated dependencies
Fixing: empty key with redis
Updated Groovy to 2.3.1
Printing full stack trace to stdout
Debug level
Merged with github/master (1.0-RC1)
Upgrading dependencies
Limiting the similar reindexation to 10

closes #25
Using expiring keys of Redis for last updated articles

closes #26
Merge pull request #24 from thepieuvre/1.0-RC2

1.0 rc2