Include `baseline-shift` CSS property

[narthur]

Property documentation:
http://www.cssportal.com/css-properties/baseline-shift.php

[cvrebert]

http://www.w3.org/TR/css3-linebox/#baseline-shift-prop

[lembitk]

+1

[Wildmage]

+1

[Didel]

+1

[neoncitylights]

+1

[fabiosantoscode]

+1

[wolthers]

+1

[giorgiofanecco]

+1

[quicksilver24]

+1

[bolvari]

+1

[klickreflex]

+1

[thomaseckhardt]

+1

[kkozuma]

+1

[wilsonminer]

+1