import/, tests/: add Ubuntu.Content compatibility layer
This is implemented as a set of QML wrappers and JS shims which exposes what QML applications expect from Ubuntu.Content types. it's not 100% the same (e.g. ContentTransfer type isn't real), but it should get most applications running.
A test is added by instructing CMake to modify the existing QML test to use Ubuntu.Content instead of Lomiri.Ccontent.
Fixes: #6 (closed)
Edited by Ratchanan Srirattanamet