* 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
@angular/http/testing used to publish a metadata structure which paralleled
the .d.ts structure. This causes ngc to write incorrect imports for this
bundle when compiling providers using MockBackend and other http testing
classes.
This change restructures the @angular/http/testing build a bit, modeling it
after @angular/platform-browser-animations, and produces a FESM structure
that has flat metadata.
Fixes#15521.
Jason Aden
Alex Rickabaugh