This enhances $.fn.positionToSide() to accept new side codes: T,

B, L, and R. These are similar to the original codes, but rather

than positioning such that the element is fully outside the anchor

element (with distances extending the element outward), these codes

position so that the positions are anchored within the element (with

distances extending the element further inward). This allows for easily

positioning (for instance) the left edge of an element 20 pixels to the

right of the left edge of another, or the bottom of an element 20 pixels

above the bottom of another.
Along with this, distances can now be set per-side, instead of only

allowing for setting X/Y distances.
These changes together allow for a lot more control over where elements

will appear in relation to other elements.
Docs have been updated to document all the options and defaults.
I've also fixed some redundant jQuery wrapping and a bug preventing this

from being used in multiple elements at once.

Verified this works with our existing calls, and tested all the new options.