Filebrowser: Multiple Connections Support #206

This also includes a fix for pinned paths on other connections than the currently active one.

The solution should be as intuitive to the user as possible. As such the following recommendation is made:

• Every storage connection gets a hash from their connection details to quickly identify them uniquely
• Only pinned paths that are associated with a saved connection may be shown in the pinned list
• Upon navigating to a directory from a different connection, the connection must be automatically made to the new storage
• This has to work well with the Tab View feature
• This behavior should include recently accessed paths and locations as well