Update filetable.py example to make it work

[stargaser]

• Fix an import bug
• Use firefly_url as an argument
• Don't launch a browser if --printurl is specified
• Pick up FIREFLY_URL environment variable if it is set
• Insert a pause after printing the Firefly URL, before uploading the table, so a user has a chance to open their browser
• Add option to sort the file paths
• Add option to prepend to the file path URLs because /external is the default mounting area for Firefly-in-Docker
• Reformat single-quotes to double-quotes to be more like black formatting
• Use black to reformat the file

[stargaser]

I'm using this to do some work for NEO Surveyor (my new position) and found a number of updates were needed.

[gpdf]

In general I think the documentation for the main() should probably include an explanation that this whole thing only works if the same directory is mounted/visible on the Firefly server.

[jaladh-singhal]

@stargaser it works great! I tested it with a local firefly server with both printurl disabled and enabled. Left minor comments, then it's ready to merge.

Also I liked that I could understand what this script does using python filetable.py --help. We should maybe document this script example in README (not necessarily in this PR though)

[gpdf]

In general I think the documentation for the main() should probably include an explanation that this whole thing only works if the same directory is mounted/visible on the Firefly server.

I think you could address this in epilog= help in the argument parser.

[stargaser]

I've added extended help to the description and the epilog. Would be great if either or both of @jaladh-singhal or @gpdf could try out filetable.py --help!

[jaladh-singhal]

I've added extended help to the description and the epilog. Would be great if either or both of @jaladh-singhal or @gpdf could try out filetable.py --help!

LGTM!

[gpdf]

Great, thank you! Looks good.