load sub html from external url

Version 1.2.5 release..

Hide all items except prev current and next slides to improve perfomance..
Reset scrolltop after closing the gallery..
Remove fadeIn fadeOut effects for IE 9 and bellow..

Version 1.2.4 release..

Merge branch 'master' of https://github.com/sachinchoolur/lightGallery

version 1.2.2 release..

Fixed sachinchoolur#167 and sachinchoolur#177.. Release version 1.2.1

updates..

Merge branch 'master' of https://github.com/sachinchoolur/lightGallery

Version 1.1.5 release..

Update README.md