New Sample - Download Image from SP Image column

[ganesh-sanap]

Q	A
Bug fix?	no
New sample?	yes
Related issues?	NA

What's in this Pull Request?

Added new sample which demonstrates adding a button within a SharePoint Online/Microsoft Lists view which downloads the image from image column.

[tecchan1107]

Thanks for amazing sample @ganesh-sanap 😍😍✨ When merging, I made a few fixes. The fixes are as follows.

• Fixed to hide the button if the Image column is empty.
• Added a few additions to the README.
• This sample is formatting for a column that requires an image column, but not a column formatting for an image column, I thought, so I added generic to the beginning of the sample name.

Please let us know if you have any questions.

I first learned how to save images with this sample! Thank you so much!!!

[ganesh-sanap]

Many thanks! @tecchan1107