Support child elements inside data-dropdown anchors

If data-dropdown anchor contains a child element (like an image for an
icon), this code will allow the appropriate dropdown functionality to
execute even when those child element are clicked.
Fixed typo on Abide page
Close background on touchend in reveal.
Remove alert.
convert index to an int, otherwise index+1 will be a string concatenation, closes #2915
fix abide sample
Fix "close" event for Reveal

Currently the "close" event is not being fired when the user clicks the
modal backdrop with closeOnBackgroundClick true, since the close event
is being triggered on the closest .reveal-modal parent of the target.
This naturally doesn't exist when the target is the backdrop.
Corrected typo on Orbit page.
Corrected Joyride typos.
Corrected Dropdown typos.
Corrected Abide typo.
Corrected kitchen sink page typo.
Corrected progress bar typo.
Corrected duplicate id on sideMainNav in global footer
Fixed a whole bunch of HTML errors in docs.
Fixed typo on Joyride page
Merge pull request #2941 from surrealist/fix-abide-sample

fix abide sample
Merge pull request #2944 from mhchen/reveal-background-close-callback

Fix "close" event for Reveal
Merge pull request #2895 from damirkotoric/dropdown-link-with-child-elements

Support child elements inside data-dropdown anchors