* Re adds svg images that were reverted earler for causing problems.
* Adds some missing rtl svg images.
* Fixes insert-ilink.svg that was causing it to not show in some browsers eg internet explorer.
User Perhelion Fixed the problem in insert-ilink.svg and insert-signature.svg. I just added it to button-sprite.svg.
Related less file adding svg to it is at https://gerrit.wikimedia.org/r/#/c/195529/
Bug: T37342
Change-Id: I14482c7b66901609689bf9ddb67b8d2add937612
