This adds the proper bindings for calling angular packages from platform-server in the UMD.
This was not a problem for universal apps that dont use UMD.
Fixes 19899
* Remove now unnecessary portions of build.
* Add a compilePackageES5 method to build ES5 from sources
* Rework all package.json and rollup config files to new format
* Remove "extends" from tsconfig-build.json files and fixup compilation roots
PR Close#18541