Disable broken tests for fileutils
Disable broken tests for fileutils

On OSX:

```
=== ERROR while installing fileutils.0.5.2 ===================================#
 opam-version 1.2.2
 os           darwin
 command      ocaml setup.ml -test
 path         /Users/thomas/.opam/alcotest/build/fileutils.0.5.2
 compiler     system (4.04.1)
 exit-code    1
 env-file     /Users/thomas/.opam/alcotest/build/fileutils.0.5.2/fileutils-76861-70a526.env
 stdout-file  /Users/thomas/.opam/alcotest/build/fileutils.0.5.2/fileutils-76861-70a526.out
 stderr-file  /Users/thomas/.opam/alcotest/build/fileutils.0.5.2/fileutils-76861-70a526.err
--- stdout ---
 [...]
 Error: ocaml-fileutils:1:FileUtil:18:Unix specific:11:Readlink (in the log).

 Raised at file "src/oUnitAssert.ml", line 45, characters 8-27
 Called from file "src/oUnitRunner.ml", line 46, characters 13-26

 expected: "/var/folders/9g/7vjfw6kn7k9bs721d_zjzn7h0000gn/T/ounit-60edff-roccapina.local#01.dir"
 but got: "/private/var/folders/9g/7vjfw6kn7k9bs721d_zjzn7h0000gn/T/ounit-60edff-roccapina.local#01.dir"
 ------------------------------------------------------------------------------
 Ran: 257 tests in: 0.25 seconds.
 FAILED: Cases: 257 Tried: 257 Errors: 0 Failures: 1 Skip:  0 Todo: 0 Timeouts: 0.
--- stderr ---
 W: Test 'main' fails: Command '/Users/thomas/.opam/alcotest/build/fileutils.0.5.2/_build/test/test.byte' terminated with error code 1
 E: Failure("Tests had a 100.00% failure rate")
```

hannesm/opam-repository,emillon/opam-repository,Leonidas-from-XIV/opam-repository,gdelaval/opam-repository,avsm/opam-repository,olgu/opam-repository,jonludlam/opam-repository,camlspotter/opam-repository,andersfugmann/opam-repository,ocaml/opam-repository,edwintorok/opam-repository,seliopou/opam-repository,nberth/opam-repository,jonludlam/opam-repository,whitequark/opam-repository,andersfugmann/opam-repository,jhwoodyatt/opam-repository,abate/opam-repository,djs55/opam-repository,cakeplus/opam-repository,AltGr/opam-repository,toots/opam-repository,samoht/opam-repository,ocaml/opam-repository,hhugo/opam-repository,mebsout/opam-repository,pqwy/opam-repository,Chris00/opam-repository,c-cube/opam-repository,astrada/opam-repository,planar/opam-repository,astrada/opam-repository,hannesm/opam-repository,mjambon/opam-repository,pirbo/opam-repository,pqwy/opam-repository,djs55/opam-repository,kkirstein/opam-repository,orbitz/opam-repository,dbuenzli/opam-repository,dsheets/opam-repository,seliopou/opam-repository,yallop/opam-repository,emillon/opam-repository,c-cube/opam-repository,def-lkb/opam-repository,UnixJunkie/opam-repository,codinuum/opam-repository,thizanne/opam-repository,hakuch/opam-repository,pirbo/opam-repository,fxfactorial/opam-repository,fpottier/opam-repository,rizo/opam-repository,Leonidas-from-XIV/opam-repository,codinuum/opam-repository,mjambon/opam-repository,lefessan/opam-repository,vprevosto/opam-repository,avsm/opam-repository,nberth/opam-repository,AltGr/opam-repository,kkirstein/opam-repository,Chris00/opam-repository,yallop/opam-repository,gfxmonk/opam-repository,camlspotter/opam-repository,jhwoodyatt/opam-repository,gasche/opam-repository,talex5/opam-repository,toots/opam-repository,talex5/opam-repository,arlencox/opam-repository,dbuenzli/opam-repository,lefessan/opam-repository,dra27/opam-repository,dra27/opam-repository,fpottier/opam-repository