Issue #1784774 by mcjim, Rob Loach: Added Assetic component to core.

core/composer.json

core/composer.lock

core/vendor/composer/autoload_namespaces.php

core/vendor/composer/installed.json

core/vendor/kriswallsmith/assetic/.gitignore

core/vendor/kriswallsmith/assetic/.travis.yml

core/vendor/kriswallsmith/assetic/CHANGELOG-1.0.md

core/vendor/kriswallsmith/assetic/CHANGELOG-1.1.md

core/vendor/kriswallsmith/assetic/LICENSE

core/vendor/kriswallsmith/assetic/README.md

core/vendor/kriswallsmith/assetic/composer.json

core/vendor/kriswallsmith/assetic/docs/en/build.md

core/vendor/kriswallsmith/assetic/docs/en/concepts.md

core/vendor/kriswallsmith/assetic/docs/en/define.md

core/vendor/kriswallsmith/assetic/docs/en/index.md

core/vendor/kriswallsmith/assetic/docs/en/introduction.md

core/vendor/kriswallsmith/assetic/docs/ja/build.md

core/vendor/kriswallsmith/assetic/docs/ja/concepts.md

core/vendor/kriswallsmith/assetic/docs/ja/define.md

core/vendor/kriswallsmith/assetic/docs/ja/index.md