Improve docume ntation for "Export" option

[agileadam]

Hello,

I may have overlooked it in the documentation, but it wasn't obvious to me that to use the "export" feature you can run sitediff diff with the -e or --export switch. For example: sitediff diff --paths-file sitediff/paths_sample.txt --export

Can you please update the documentation to make this obvious?

Thank you!

[kirk-brown-ew]

We are working on improving our documentation and we'll look into the export feature.

[kirk-brown-ew]

Updated content in 1.2.3.