Merge pull request #10 from AntoineNeveu/master

Addition of permission's category management
Merge pull request #11 from AntoineNeveu/master

JSONViews, BeanValidation and user genericity added
Upgrade to RESThub 2.1.0-SNAPSHOT
Remove ElasticSearch integration from core and move it to webapp
Move from home made Observer pattern to Spring bultin mechanism. Also set minimum Java requirement to Java 6 (was previously 7)
Filename refactoring and js fix
Filename refactoring
Replace category by hierarchical permissions
Make role and group generics, like it has been done for user (+ various refactoring and cleanup)
Manage applications, with a non final implementation of per application permission filtering
Merge pull request #12 from sdeleuze/master

Application management + various refactorings