Due to a change to PY3, the charmhelpers directory is not in the
CHARMDIR rather than in CHARMDIR/hooks. This broke the
copy_nrpe_checks() function in c-h. c-h has been updated, to look in
both CHARMDIR and CHARMDIR/hooks for the charmhelpers directory, and
this patchset includes the new function definition.
Change-Id: Ifc0baabee4e06b79015e02b95634bce879ae84af
Closes-Bug: #1796830