Split user.js into separate files

[Kakadu]

And build final one using make user.js. At the moment it generated exactly same config as current user.js

This will allow us to apply fixes for the config without touching original config. Can be useful

• for maintainer when adding changes for the config from master branch
• for users by overriding some parts of config to repair broken web-sites.

@pyllyukko

[Kakadu]

@pyllyukko Do you have any thoughts about my idea?

[pyllyukko]

@pyllyukko Do you have any thoughts about my idea?

Sorry this has been pending. Not splitting it up at least now.