Stats

[gabelula]

What does this PR do?

• Moves stats into a package stats in /pkg
• Use Cobra to add a command line tool to run stats
• Adds CalculateStats to the cron jobs inside Pillar

  How do I test this PR?

To run the command line tool:

• cd cmd/stats
• go build
• ./stats -h

To get the cron job running:

• set env variable PILLAR_CRON="true"
• run pillar

@coralproject/backend

[gabelula]

@jde ready for review. Not sure why it added some commits by you (I used an old branch 'stat's... but I merged master into it).

[jde]

Approved.