Royal Mail postage size guide, 2013

A new size guide for Royal Mail letters and parcels, including a third slot for the new _Small Parcel_ category.

This guide has:
* Measuring slots for width and height
* Outline profiles for width and length
* Coverage of _Letter_, _Large Letter_ and _Small Parcel_
* Price guides by weight, as of May 2013
* A handy ruler

Great for eBay sellers, or anyone sending lots of variously-sized parcels..

There are two drawings included here: a three slot version and a two slot version, for those with smaller lasers, or who just need the letter sizes. For most of us, letters are either "Put a stamp on it" or "Take it to the Post Office", so we really just need those small "stampable" slots.