Gather metrics on shipped packages

This commit adds data collection to the uber_ship task,
as well as reworking the 'add' and 'post' metrics tasks specifically
for data relating to shipped packages.
Remove old metrics gathering methods

This commit removes the old, unused metrics gathering methods along with
every instance in which they were called.
Merge pull request #187 from Whopper92/shipped_metrics

Gather metrics on shipped packages