Handle specific Debian path: /etc/init.d/ssh instead of /etc/init.d/sshd
(cherry picked from commit ed86022ae438926930224f789b0da486bdeed171)
cfengine_stdlib.cf: split into 3.4/3.5/3.6 versions.  Add sys.cfengine_version_{major,minor,patch} and use it to load the right libraries for 3.6 and later.  Split by promise type for 3.5 and 3.6.
(cherry picked from commit b87b46ba213d23284635b5aa68cc1f9fbdca318f)
ChangeLog entry for stdlib split (#3044)