Collect statistics for gauge commands

[zabil]

If a user opts-in to send usage information.

Collect statistics of gauge commands execution to improve or deprecate command line options.
The statistics will be collected via google analytics using measurement protocol

This must exclude user identifiable information like ip and user specific parameters like spec folders

$ gauge myspecfolder

Must not record myspecfolder.

or

gauge --dir="../"

Must exclude directory information.

[sriv]

The default behaviour shall be "opted in", with options for the users to disable these pings. This is so that unattended execution of gauge is not left out.