gui: Fixed RepetitionSelectOverlaybug where sometimes one grid line went missing
gui bugfix: the gallery tools now get reset when new data is displayed (and not just when a file is opened), so overlays are also cleared after acquisition
gui: focus border fix for AngularResolvedView
gui: ZeroDimensionalCanvas bug fixed, where interpolation of the x value always occured
gui: If a Slider is set to a value outside of it's range (which comes from the GUI config, *not* the hardware range\!), it will set itself to its maximum or minimun value and fire a change event. This event will cause the associated VA to be set to that value
gui bug fix: The thumbnail update method of the MicroscopeCanvas can no longer cause dead object exceptions
gui: Prevent tab switching during acquisition
Merge branch 'master' of 192.168.92.5:odemis
gui: Encoding fix
gui: Prevent GUI exit while acquiring image
Merge branch 'master' of delmic-server.local:odemis
gui: Tab lock fix
gui: The SPARC acquisition tab is now fully disable during the actual acquisition, except for the cancel button.
gui: *Real* slider value fix where the minimum and maximum values are adjusted when a value that is out of range is set
gui: Added 'Region of Drift Correction' tool to the SPARC Acquisition tool menu
driver semcomedi: new "park" parameter to specify special voltages to use when not scanning

From an idea of Martijn.
These values can be bigger than the normal values, just need to be within the electronic range.
gui: fix typo in combobox

wx.Window.Enabled is a property, no need to call it.
gui acquisition: set is_acquiring to False as soon as acquisition is done

It would otherwise miss the cases where the acquisition failed/was canceled, which prevented to ever close the GUI again.