Unlinking assets from devices (and searching for unlinked assets) is now
possible.
Fixed previous commit for unit tests (test_form_with_ralph_device_id).
Code review fixes.
Resolved merge conflicts.
Added searching assets by ralph_device_id. Added option to create stock
devices for unlinked assets.
Updated changelog.
Merge pull request #52 from xor-xor/t1385

Unlinking assets from devices (and searching for unlinked assets) is now possible.