Adds builder as separate package

[NothingEverHappens]

No description provided.

[kirjs]

Now builder is treated as a separate package an has it's own binary.

This is how you debug it:
node --inspect-brk ./node_modules/.bin/builder-30-seconds serve

[fetis]

node --inspect-brk ./node_modules/.bin/builder-30-seconds serve

I think we need to add DEVELOPMENT.md and add this line there

[fetis]

generally, looks good to me.

I think 2 things missed (can be added in next PRs)

1. styles are still served from builder directory
2. instead of picking up config from config folder, specify file as parameter with some defaults