we don't need to check if one or the other in this
.is() is as much as 3x faster then .hasClass()
.is() is faster then .hasClass()
again .is() is faster then .hasClass()
another hasClass replacement
no reason to find the `.unshelved` from the spine cache, just go stright to it
we can use the :not() over .not() which is faster
Merge pull request #148 from washingtonstateuniversity/js_refactors_for_1.2.0

Js refactors for speed