make the lite in netprobe_lite mean something ;)

[NicolasCARPi]

this change brings the size of the image from 561MB to 173MB

• add comment header
• use slim tag from python official image
• use apt-get clean
• disable pip version check

[NicolasCARPi]

Hello,

Very cool app, please consider this change and #23, too.

Regarding the Dockerfile, this first changeset is pretty minimal, but already has a huge impact on the image size!

If you want, I can go further, by using a builder image, a virtualenv, using non-root user (could this be an issue?). Similar to this one: https://github.com/manulera/ShareYourCloning_backend/blob/master/Dockerfile

Cheers, ~Nico

[plaintextpackets]

I will definitely test this out for a future release, I stuck with Ubuntu to start as it worked but eventually would want to slim it down as much as possible. Appreciate it!