Build: Setup bower package

Using native bower setup due to issues with grunt-bowerful
Build: Remove grunt-bowerful and use native bower

Extended the postinstall hook to install the 2 required global modules
(grunt-cli and bower) and install all the bower packages.
Related to gh-2914
Data-inview: Cleaned up several validation errors in the working example HTML.
Merge pull request #2924 from pjackson28/cleanupdatainviewhtml

Data-inview: Cleaned up several validation errors in the working example HTML
Cleanup the base HTML a bit. Cleaned up incorrect heading structure and excessive use of sectioning elements.
Merge pull request #2926 from pjackson28/cleanuphtml

Cleanup the base HTML a bit. Cleaned up incorrect heading structure and excessive use of sectioning elements
Aligned base HTML more closely with the v3.1 HTML in terms of sectioning elements, headings and WAI-ARIA landmarks. Now has proper HTML5 outline.
Merge pull request #2928 from pjackson28/htmlwork

Aligned base HTML more closely with the v3.1 HTML in terms of sectioning elements, headings and WAI-ARIA landmarks. Now has proper HTML5 outline.
Fixed CSS in data-inview to react correctly with state changes of designated elements.
Merge pull request #2919 from nschonni/native-bower-setup

Build: Native Bower setup
Removed jQuery Mobile markup and associated headings to sectioning elements using aria-labelledby.
Merge pull request #2932 from pjackson28/addarialabelledby

Removed jQuery Mobile markup and associated headings to sectioning elements using aria-labelledby
Build: Install latest node-sass under grunt-sass

Temporary workaround till the updated node-sass npm package is released
with the fixed Windows binaries
Merge pull request #2941 from nschonni/v4-tarball-install-node-sass-temp-fix

Build: Install latest node-sass under grunt-sass
Carousel: Rename template to 2 digit lang code
Merge pull request #2927 from masterbee/data-inview

Fixed CSS in data-inview to react correctly with state changes
Build: Remove node-sass upstream download

0.6.5 release includes the fixed binaries now
Merge pull request #2942 from nschonni/rename-carousel-template-language

Carousel: Rename template to 2 digit lang code
Build: Cleanup unminified files after Uglify
Merge pull request #2945 from nschonni/cleanup-js-after-minify

Build: Cleanup unminified files after Uglify