New sampling devices handling
The selection of the sampling device in the "Sampling device control" section is now done via a dialog that opens when the change push button is clicked (hand icon). The list of devices is updated with changes when plugins take and release devices or channels inside devices therefore you only see what is available at any one time. For multiple channel devices like the LimeSDR that is 2x2 MIMO you can now select the second Rx or Tx device directly even if the first is not used. This implements issue #52
Details described here: https://github.com/f4exb/sdrangel/tree/master/sdrgui#3-sampling-devices-control
As it is a fairly important change in the UI this motivated the minor version upgrade.
Non functional changes
Further work on separating the GUI from the core application. This was facilitated actually by the main feature of this version described previously. A lot of code cleanup could be made in the PluginManager removing non relevant code. The channels processing was also reworked repatriating code in the non GUI base library (sdrbase).