Restore the original video tag attributes on a tech change

set attributes of video tag and not only values

add unsupported attribute to the video tag - test failing

helper to set attributes on an element from a map of values

dummy compare of html content with a sort of the attributes

ignore html attributes order for comparition

save original tag attributes

restore original tag attributes n creation and overwrite if required by settings

replace object.keys with vjs.obj.each for ie<9

fix spacing

API consistency, getAttributeValues renamed to getElementAttributes

clear variable naming

move setElementAttributes close to getElementAttributes
Maded some revisions to videojs/video.js#1369

closes #1369
Added line to changelog for #1369