DGM-65 initial code for backup a queue to disk.
DGM-65 code for in order queueing
DGM-65 return value of delete()
DGM-80 retry limit
DGM-65 check file every 2 seconds.
DGM-65 path separator
Merge branch 'master' of git://github.com/ricojansen/elasticsearch-degraphmalizer

Conflicts:
	src/main/java/org/elasticsearch/plugin/degraphmalizer/Updater.java
	src/main/java/org/elasticsearch/plugin/degraphmalizer/UpdaterManager.java