Improvements on receiving images

Description

Just some thoughts on improving the experience of receiving images in Flare:

1. Clicking on the small image shown in the chat window should expand the image to the full size of conversation part of the window, like in a "lightbox" on a website (on top of the text) – with an option to zoom and drag, and close the "lightbox" with the image by pressing Esc or clicking an X button.
2. First time downloading an image the file selector should default to the Downloads folder, not the home folder
3. On consequent downloads the file picker should remember where you downloaded the last image. Ideally it should remember it pr conversation.

That's my thoughts on this so far. Thanks!