#209 Sharing button is added, save-bug is fixed

- Sharing-button is added to support the share button
  (Currently url is hard-coded as 'http://example.com/"recording-group-id"')
- Save bug is fixed
- Obtaining location data is changed to 3 stages
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  1) make the best location-provider start gathering location data.<br/>
  2-1) if the location data is obtained, return it.<br />
  2-2) if recording is finished before the location data is obtained, return the last-known location(out of date).<br />
  &nbsp;&nbsp;2-2-a) if the last-known location is also not available, return (0, 0).
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