Update gulpfile.js and package.json

Dependencies were updated
Deprecated use was removed in gulp
Refactor tests, make them green!

Now use two modes for each tests with a function, instead of repeating the same test twice
Merge pull request #14 from saveman71/improve-index.js

Improvements for index.js
Merge pull request #12 from saveman71/gulpfile-improvements

Update gulpfile.js and package.json
Merge pull request #13 from saveman71/refactor-tests

Re-factor tests
0.4.7