OTC: Manually port toolslive/camltc@7cb58b75bf99bd95cea1766262a8bbc320ca8104

Original commit:

    commit 7cb58b75bf99bd95cea1766262a8bbc320ca8104
    Author: Jan Doms <jan@jan>
    Date:   Tue Mar 19 12:48:40 2013 +0100

    ARAKOON-368: rev_range_entries returns incorrect result if parameter
    'first' does not exist as key in the database
OTC: Manually port toolslive/camltc@f017df6f5917041b01b32c3c27a4c943949970d7

Original commit:

    commit f017df6f5917041b01b32c3c27a4c943949970d7
    Author: Jan Doms <jan@jan>
    Date:   Wed Mar 20 15:12:15 2013 +0100

    processed feedback
OTC: Manually port toolslive/camltc@047b41c5971e01a5a814c155f1083b1ce1f9a3e0

Original commit:

    commit 047b41c5971e01a5a814c155f1083b1ce1f9a3e0
    Author: romain <romain@romain-laptop.(none)>
    Date:   Thu Mar 21 16:16:02 2013 +0100

    extra test case for rev_range_entries (this one used to fail)
system test for ARAKOON-368
(cherry picked from commit 8898aaee802941ac88f31e4b9e1ea0aabc91b7bd)