Add typed gulp-html-angular-validate

[tdbrian]

Filling in these fields will make it easier for us to review:

Typings URL: https://github.com/tdbrian/typed-gulp-html-angular-validate
Source URL: https://github.com/ewu02/gulp-html-angular-validate

Thanks for contributing!

[blakeembrey]

@tdbrian I think you want to unwrap https://github.com/tdbrian/typed-gulp-html-angular-validate/blob/master/index.d.ts from being inside declare module. This won't work when you install it otherwise.