Allow to keep generated files in setup-dev and fallback if oasis not present

[gildor478]

This feature request has been migrated from artifact #900 on forge.ocamlcore.org. It was assigned to user102.

user102 posted on 2011-01-31 09:26:32:

Some project need to have a standalone build system commited in their VCS (e.g. ocamlify). In this case, it would be better to commit files generated by setup-dev and fallback to standard setup procedure if "oasis" exec cannot be found.