feat(replication): Help user when error due to `ulimit`
feat(replication): Help user when error due to `ulimit`

Some errors like `no_ring` or `no_majority` can happen when the number
of open files is too high. In such cases, it is hard to understand why
it is failing (there's a clue in CouchDB logs).

Help users by printing a message for that.

adrienverge/coucharchive