Enhance Exif Data values and display

[astroman133]

Here are some suggestions related to improving the usefulness of the EXIF data that BYE/BYN adds to images, and to make the display of that data more useful.

1) An EXIF value named "BackyardCaptureDate" is saved. It is not clear from the name whether this is based on the capture start time, the capture end time, the image download time, or the file creation time. My suggestions are to change the name of the parameter to indicate the point in the capture process that it represents. Something like "BackyardCaptureStart" removes the ambiguity. I would also suggest increasing the resolution to include milliseconds. It should be consistent with the Timestamp field in the file name. I should note that this would be a breaking change for any user or application that is extracting and using BackyardCaptureDate, so you may want to get consensus from the community or simply add BackyardCaptureStart as a new EXIF value.

2) Add additional EXIF values, with similarly unambiguous names to represent the capture end time, image download time, and file creation time.

3) Improve the Exif Data dialog window to either 1) allow the window to be re-sizeable and/or 2) present the user with a horizontal scrollbar. It should be easy to do both by making the horizontal scrollbar visibility be Automatic so it is displayed only if needed. The initial size could also be specified as the window's minimum size so the user could make the window larger, but not smaller, than the initial presentation.