added support for selectTag to accept an array of selectedOption
if select is in multiple mode, every selectedOption is selected
if select is single mode, only the first selectedOption is selected

added related tests
Updated docs for selectTag supporting array of selectedOption

as in commit e95eb4493e827994a24f1b923590891c0802c4eb
Merge pull request #531 from wstucco/selecttag-array-of-selected-options

added support for selectTag to accept an array of selectedOption