Add file proxy icon

[s2b]

In addition to #4, it would be great if you could add the file proxy icon in the title bar if the markdown comes from a file. This would allow various drag&drop file actions from within mud.

[joseph]

Yes, thanks, I'll get this into the next release.

It will be the file proxy icon, which is straightforward, but not the "document title menu" (where you can click on the file name to rename it or add tags or move it or lock it) — that would be a substantial amount of work and change.