feat(infrastructure): add esmodules support for treeshaking (#4409)

Author: Matt Goo

.gitignore

@@ -14,6 +14,9 @@ node_modules/
 /build/
 /coverage/
 packages/*/dist
+packages/**/*.js
+packages/**/*.d.ts
+packages/**/*.map
 
 # Material.io site generator test (`npm run test:site`)
 .site-generator-tmp/

.travis.yml

@@ -41,7 +41,7 @@ matrix:
     env:
       - TEST_SUITE=build
     script:
-      - if has_testable_files; then npm run build; else log_untestable_files; fi
+      - if has_testable_files; then npm run dist; else log_untestable_files; fi
 
   - node_js: 8
     env: