v1.3.0

• allow getting and setting gain of specific amplification elements (get_gain and set_gain methods), you can also pass dict with specific gains to constructor (e.g. gain={'LNA': 28, 'VGA': 12, 'AMP': 0})
• listing, getting and setting SoapySDR device settings (list_settings, get_setting and set_setting methods), you can also pass dict with specific settings to constructor (e.g. settings={'biastee': 'true'})
• stream and stream_timeout are now public (it was _stream and _stream_timeout before)
• all properties (like freq, sample_rate, etc.) now returns actual values from device (not cached values)