Bundled types (.d.ts) in npm package

[pmstss]

Pull Request Description:
I've enabled d.ts generation in tsconfig.json, then added and configured DtsBundleWebpack plugin to generate d.ts bundle compatible with npm publishing. typings property in package.json is adjusted too.

Motivation:
Utilize types power in pretty complex jsPDF-AutoTable config without import of source files. Currently in project I have to had something like:

import { Cell, Table } from 'jspdf-autotable/src/models';

which is generally bad practice and causes issues with tsc.

[pmstss]

Not that easy :( Trying to find workaround for TypeStrong/dts-bundle#57

[simonbengtsson]

This is great! ❤️

[pmstss]

Was not able to tame dts-bundle/DtsBundleWebpack plugin.
More straightforward way would be add auxiliary file with all exports and skip bundling (will have multiple d.ts files in ./dist).
Will submit new PR soon. :)