cannot recover syntax errors from why3 ide in external editor
(Regression with respect to previous behavior)
When opening "why3 ide", syntax errors now show in the IDE itself, so we can't recover them easily within an external editor (for example emacs+next-error). Also, the IDE now opens even in the presence of such errors, which force the user to discard the window before coming back to his/her editor. This makes much harder to use Why3 unless through the integrated editor, which is not convenient for everyone.