[RFR] Add a mutex in RouteParametersConverter (follow #38)

This PR aims to synchronize all calls to the API. Indeed at each load there are two requests on the API for the current node (the tree view and the property view). That means that the cache strategy is not working well. 
But to fix it, we have to ensure that a call to getCurrentNode is not completed until the previous one is done (to let the cache to be filled). 
The method getCurrentNode relies on getRepository so I had a mutex in this last one.

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Finally AngularJS handle the mutex case but do not invalidate cache when we force cache=false on a specific request. That why we need to manually invalidate it.

- [x] Fix cache strategy