publish docs package as standalone theme

[giladgray]

After #796, we'll be using documentalist to build the docs data and the docs package to render it. Next big step is to package up the docs package so it can be used OOTB as a theme for (a particular configuration of) documentalist.

This includes:

• move custom code out of docs package (to site-docs)
• use tsc build like other published packages
• make docs package publishable
• what to do with layout code currently in blueprint gulp task? moved into DM

[brsanthu]

While we talking about the docs package, is it possible to extract the nav menu as a component? it is really nice :)

[giladgray]

@brsanthu unfortunately no, as the NavMenu is quite specific to the documentation context: its interface only makes sense when you've got data in the exact format that our tooling produces. (it's nothing more than a recursive renderer for a nested tree structure.)

on the other hand, the forthcoming published docs package will include a host of documentation components that can be reused, assuming you've got data in the correct format.

[giladgray]

shipped in v1.14.0!