Cleanup.
Starting to code new system directory provider.
Making the application resilient to the fact that the data save dir could not exists or can't be created.
Using new SystemPaths.getTemp() and refactor to setup the temp folder.
Minor cleanup.
Optimization to save resume data with less frequency with the same result.
Throttling save resume data in case pieces are created too small or close to a block.
domain fetcher update
initial btdigg implementation

* depends on frostwire-desktop search-engines branch
* sends GET request to api.btdigg.org and decodes response
* de-serializes JSON response and passes objects to GUI
* many breadcrumbs left behind
fix hidden results bug - add tests and callchain doc

* depends on search-engines branch of frostwire-desktop
* allowed search results to display in the GUI
* added documentation for the call chain initiated by search queries
* added some simple GUI acceptance tests

NOTE:
  results were hidden because a valid filename extension is required
    for a proper result but this is not enforced and so was not obvious
    the source of this bug took some digging to uncover and resulted in
      the callchain document included
    the BtDigg results do not contain any filenames only magnet links
      so this was kludged for now