Replace TemplateItem with SensorTemplate in the sensortemplate.json and
json ctest. Change to contributions.md which removes all objects
with a key starting with "//" from the generated sensor .json file.
This allows the json ctest to pass OOTB for new sensor libraries
generated from the make_new_sensor function.
Signed-off-by: Noel Eck <noel.eck@intel.com>