[INSTALL] Add troubleshooting instructions
[INSTALL] Add troubleshooting instructions

When worktree is dirty, some additional steps might be necessary, if the
developer is touching a part of the code that regenerates OCaml output.

Signed-off-by: Ramkumar Ramachandra <5c355d1d38066ed0c5de420d67c1b5ed0687c4bd@gmail.com>

FStarLang/FStar,A-Manning/FStar,A-Manning/FStar,A-Manning/FStar,FStarLang/FStar,FStarLang/FStar