Converted doxygen style comments to reStructuredText style in the files found in Cura/cura/API directory recursively using the script dox_2_rst.py (provided in the Uranium repo). Comments were manually checked and changed if needed.
Comments from the hidden attributes in the class CuraAPI (_acount, _backups, _interface) were moved to the public property getters, so they docstrings are exposed to the user.
If it's not used that way we want to know about it and fail.
If plug-ins use it this way, the plug-in won't get initialised so it'll be as if the plug-in is disabled or that function doesn't work.
Contributes to issue CURA-7135.
