Expose metering in api extensions section

The section content was here, but not exposed to the extensions list.

Change-Id: I764ae7ba1bb8cb3d75be69d245afb285a6a292fc
Closes-bug: #1229389
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>
Merge "Expose metering in api extensions section"