— procedure: get-stable-release-from-server-string str

Is this true?

— procedure: get-stable-release-from-coot-version

Needs testing.

— procedure: notify-of-new-version str

show the dialog

— procedure: download-binary-dialog

version-string is something like: "coot-0.6-pre-1-revision-2060"

— procedure: directory-is-modifiable? prefix-dir

Test for prefix-dir 1) existing 2) being a directory 3) modifiable by user (ie. u+rwx)

Return #t or #f.