Add finer-grained options to fstar-jump-to-errors
Add finer-grained options to fstar-jump-to-errors

The new default is to jump to errors only; the old default is available as
‘errors-and-warnings’. nil means the same as it used to.

Suggested-by: da39a3ee5e6b4b0d3255bfef95601890afd80709@beurdouche

FStarLang/fstar-mode.el,FStarLang/fstar-mode.el,FStarLang/fstar-mode.el