style: prepend Google @license to all files

[theefer]

Prepends the standard @license doc to all .{js,ts} files that didn't already have one.

[clydin]

Schematic template files shouldn’t have licenses. They’re part of the user’s application.

[theefer]

Ah you're right. I've reverted all files in packages/schematics.

[hansl]

Cool. Thanks. Every files in angular-cli-files were not under the same licensing rules, so we kind of forgot about those.