MODE-2299 Upgraded HttpClient and dependencies to 4.3.5

Added an additional commit which adds an integration test around WF/EAP integration and the `FileSystemConnector`.

@rhauch: if possible can you pls try to cherry-pick the [2nd commit](https://github.com/hchiorean/modeshape/commit/aa473b548d7ced69bfe0ac51da74556416140978) into the `3.x` branches ? IMO it's a good test case to have in all branches.