Merge branch 'multilabel' of https://github.com/abifet/moa

Conflicts:
	moa/src/main/java/com/yahoo/labs/samoa/instances/InstanceImpl.java
Merge branch 'master' into amrules
Merge branch 'multilabel' of https://github.com/abifet/moa

Conflicts:
	moa/src/main/java/com/yahoo/labs/samoa/instances/InstanceImpl.java
Merge branch 'master' into amrules
Updated AMRules model description