suggestion: image upload for forum

[FabriceNeyret]

to show images on the forum, especially grabs to show bugs to a shader writer, we have to save the image locally, upload it to some hosting site like http://www.hostingpics.net/ , get a direct usable link, then in shadertoy forum enter [img] url [/img] ( without error or it display wrong and there is no delete button). -> it would be great to ease user work here.

suggestion 1: add an "insert image" button, that open a file requester and manage sending image to some hosting site then create the [img]...[/img] entry in the forum.

suggestion 2: add a "insert grab" button that grab shader image, send it to some hosting site then create the [img]...[/img] entry in the forum.