This update for python-usbsdmux fixes the following issues:

- Update to 0.2.1. Main changes:

  * cli: Handle well-known Exceptions
  * usb2642i2c: Do not create if device node does not exist 
  * commandline: 'get' must respect hardware signal priority

- Main changes in 0.2.0:

  * Remove the service/client split and access /dev/sg* directly
  * usb2642i2c: Fix sg device open arguments
  * Simplify the read-only to read-write mode transition
  * usbsdmux: honor wait argument in mode_disconnect()
  * main/service: add get action
  * usdbsdmux: set/enable default output values only for writes

- Move udev to a separate package
- Use update-alternatives

- Add udev rule to have /dev/usb-sd-mux/id-<SERIAL> links

- Version 0.1.8