Update the info about what js scrips you are using (mmistakes#2276)

Added Smooth Scroll and Gumshoe info

Author: Luis Puerto

README.md

@@ -187,7 +187,8 @@ To test the theme, run `bundle exec rake preview` and open your browser at `http
 - [Magnific Popup](http://dimsemenov.com/plugins/magnific-popup/)
 - [FitVids.JS](http://fitvidsjs.com/)
 - [GreedyNav.js](https://github.com/lukejacksonn/GreedyNav)
-- [jQuery Smooth Scroll](https://github.com/kswedberg/jquery-smooth-scroll)
+- [Smooth Scroll](https://github.com/cferdinandi/smooth-scroll)
+- [Gumshoe](https://github.com/cferdinandi/gumshoe)
 - [jQuery throttle / debounce](http://benalman.com/projects/jquery-throttle-debounce-plugin/)
 - [Lunr](http://lunrjs.com)
 
@@ -243,9 +244,13 @@ Minimal Mistakes incorporates [Magnific Popup](http://dimsemenov.com/plugins/mag
 Copyright (c) 2014-2016 Dmitry Semenov, http://dimsemenov.com.
 Magnific Popup is distributed under the terms of the MIT License.
 
-Minimal Mistakes incorporates [jQuery Smooth Scroll](https://github.com/kswedberg/jquery-smooth-scroll),
-Copyright (c) 2017 Karl Swedberg.
-jQuery Smooth Scroll is distributed under the terms of the [MIT License](http://opensource.org/licenses/MIT).
+Minimal Mistakes incorporates [Smooth Scroll](http://github.com/cferdinandi/smooth-scroll),
+Copyright (c) 2019 Chris Ferdinandi.
+Smooth Scroll is distributed under the terms of the [MIT License](http://opensource.org/licenses/MIT).
+
+Minimal Mistakes incorporates [Gumshoejs](http://github.com/cferdinandi/gumshoe),
+Copyright (c) 2019 Chris Ferdinandi.
+Smooth Scroll is distributed under the terms of the [MIT License](http://opensource.org/licenses/MIT).
 
 Minimal Mistakes incorporates [jQuery throttle / debounce](http://benalman.com/projects/jquery-throttle-debounce-plugin/),
 Copyright (c) 2010 "Cowboy" Ben Alman.