fix(device-view): set icon to MicroDrop icon
fix(device-view): set icon to MicroDrop icon

Prior to this commit, the `bin.device_view` window icon was set using a
regular file path to the MicroDrop icon.  However, this approach to icon
loading breaks if the `microdrop` Python package is loaded from within a
`.zip` archive (e.g., in an application bundled using Py2Exe).

In this commit, load the MicroDrop icon using `pkgutil.get_data`, which
also supports loading from within a `.zip` archive.

wheeler-microfluidics/dmf-device-ui