beta: auto update Parsoid dependencies using npm

The Parsoid daemon relies on JavaScript dependencies defined in
mediawiki/extensions/Parsoid.git in /js/package.json.

In production they are hold in a private repository on tin.eqiad.wmnet
under /srv/deployment/parsoid/config. For beta we are simply going to
brute force 'npm install' whenever the beta-code-update job is running.

I forced the color parameter since Jenkins is smart enough to translate
ANSI escape codes to HTML, providing a better user experience.

Change-Id: If831732b333c7bd825b0f80628af1d28e3b4bf2e
Merge "beta: auto update Parsoid dependencies using npm" into production