Merge pull request #698 from peircej/master

Added option to select subset of conditions in Builder in various formats
Merge pull request #699 from peircej/master

PEP: values should be compared to None using `is` not `==`
BF: linux issue with wx3.0 and drag-drop of files onto coder

Don't use DragAcceptFiles(True). That was only really for windows and now raises an error under linux