graphviz: fix ob.target is undefined error
graphviz: work on aggregation
graphviz: aggregation ranking
graphviz: optimize node content retrieval
graphviz : enlarge root node
graphviz : can delete nodes from graph
graphviz : can delete aggregation nodes
graphviz: begin node loading
Added safeApply to rootScope
graphviz: somewhat of a Hash::Merge
graphviz: load node relations on click
graphviz: optimize cypher request (do not retrieve <<INSTANCE>>)
grahviz: keep the right relations directions
graphviz: limit cypher query to current topic
graphviz: first shot at aggregation bubble explosion
Proportional sizes
Merge branch 'feature/graph-visu' of github.com:jplusplus/detective.io into feature/graph-visu

Conflicts:
	app/detective/static/detective/js/directives/graphviz.coffee