Various improvements

as described in the added CHANGES file, I exported the helper functions as $. methods, which allows formatting of strings without being bound to page elements.  Also expanded the map of supported currencies, fixed a few as to position and spacing, and restructured the code a bit for greater maintainability and performance.

It's my first pull request so if I botched it, please help!

thanks,

- ekkis

p.s. also added a TODO file with other issues I'll be working on...