Add base dialog class that can be used to implement responsive JS dialogs.
Fix typo.
Remoev unused showBodyChildren() function and update updateLayout() function name.
Switch full_screen config to resize_mode and add a centering mode.
Only udpate positioning if the dialog is open in resize handler.
Move dialog header into scrollable element for dialogs.

This works much better for mobile.
Fix overzealous scroll-top behaviour.
Fix bad comment.
Add todo comments for animations.
Better respond.js load detection for IE8.
Fix edge case that caused dialogs to rremain hidden after updating layout.
Merge pull request #93 from gauthierm/site-dialog

Add base dialog class that can be used to implement responsive JS dialogs