phylocsf FTBS

[osallou]

phylocsf fails to build from scratch

....
+- The following actions failed
| - build ocaml-system 4.02.3
+- 
+- The following changes have been performed (the rest was aborted)
| - install base-bigarray base
| - install base-threads  base
| - install base-unix     base
+- 
# Run eval $(opam env) to update the current shell environment
Switch initialisation failed: clean up? ('n' will leave the switch partially installed) [Y/n] n
The command '/bin/sh -c opam init' returned a non-zero code: 31