[oe] script to remove orphaned files

[Frans Meulenbroeks]

Dear all,

I just pushed the last batch of changes.
All recipes dirs have been cleaned except for boost (someone
explicitly asked not to clean it; if I recall correctly because he was
working on that recipe and that patch).
Should something have been moved that should not be moved, feel free
to revert the patch or restore the missing file from obsolete.

I would appreciate it if people would check every once-in-a-while if
they do not leave stale files behind.
A maintainer of a recipe is in a much better position to judge this than I am.

Also please note that I am not saying that there are no unused files left.
A few recipes used things like ${PV} in the patches. I did not process
these dirs.

Furthermore I did not analyse file paths or so. I've taken a cautious
approach, so if a patch file was referenced in any bb or inc file from
that recipe it was kept as it was too hard to reliably judge if *that*
copy was actually used.
So e.g. if you have v1/patch and v2/patch both files are still there
even though maybe only v2/patch was used.
Doing that kind of cleanup would require a recipe parser that marks
all files that it uses.
(and if someone can create such a thing, that would be nice).

Best regards, Frans.