Added preloader and other minor changes

* Added 1 additional background image
* Compressed all images to save bandwidth
* Added an hidden image for social media sharing purpose.
* Made About Ayoola title a bit augment and darker in color.
* added bottom margin to about-ayoola dropdown window
* Added background colour to homepage
* Changed "About Ayoola" menu background color to reflect general link
colour
* added a preloader to show image loading. Similar to Youtube style.
* changed top social icons margin-top to 2em to allow space for
preloading bar
* Changed version number and update readme file
* Position LIM Concepts footer message correctly on all devices
* Changed CSS file structure to be implemented from Grunt file
* LESS files will be @imported inside app.less file
* Updated nprogress.css to less file and dynamically changed colour