Replacing public with private.key filename on page 5 in user guide.
Replacing public with private.key filename on page 5 in user guide.

Signed-off-by: Ulf Hofemeier <0f9c85569455edd643178ea6cb9204b635b5e463@intel.com>

Ylianst/MeshCentral,Ylianst/MeshCentral,Ylianst/MeshCentral