Added a method to clear the remote device lists for all loaded backends

Temporarily install twomemo and oldmemo from their git repositories t…

…o allow the tests and publish to work

Prepare version 1.3.0 release

Prepare v1.2.0 release

Re-releasing, minor version bump

Add new method for manual device list refresh accross all loaded back…

…ends, prepare release

Prepare version 1.0.4 release

Slightly modified docstrings to avoid weird sphinx warning

Clarified download failure exception semantics

Prepare release 1.0.1, clean up test-related sections of the README