Implemented a DICOM tree using pydicom and PyQT5

[bastula]

Is there an issue this contribution addresses?

What contibution are you adding? How do we use it?

• This example just requires PyQT5. PyQT5 requires Python 3.5 or later.
• Testing was performed on Python 3.6 on Mac OS 10.13 and Python 3.7 on Windows 7.

Any other comments?

• [x] I have added a single script or subfolder to a topic folder
• [x] I have added some form of documentation and my contact with the contribution
• [x] I have added a link to the contribution in the topic folder's README.md