change jquery version to 1.x (IE +)
refactoring code, to support IE8
Revert "refactoring code, to support IE8"

This reverts commit 8b7969c67e67ed1a638773620548eefd22638ace.
Revert "change jquery version to 1.x (IE +)"

This reverts commit e333fd6d233e4b7d3cabc100e771acc04abe2123.
performance improvements, IE polyfill for last-child