Fixes #4899: Upgrade to CFEngine 3.6.0rc2

Co-Authored-By: Matthieu CERDA <matthieu.cerda@normation.com>
Merge pull request #329 from Kegeruneku/int_4899/upgrade_to_cfengine_3_6_0rc2

Fixes #4899: Upgrade to CFEngine 3.6.0rc2