Update whitespace & braces to WP Coding Standards

Just a bit of nit-picking related to WP coding standards. No
functionality has changed.
Fix some conflicts
Don't show transaction results if the viewer didn't make the transaction.
Fixing small errors in USPS settings page
The label on the USPS shipping options didn't match the input id
because of what seems like a typo. That's fixed. I also fixed the
shipping options not reflecting in the form properly, by casting the
returned value of array_search (the index it was found at) to a bool
to make it comparable internally in the checked() function
Port WPSC_Product class over from the new theme engine
Stats API for products and purchase logs
Get date range stats for individual products and collections
Fix PHP notice
`$this` should be `$log` in _wpsc_action_update_product_stats()
Use the get_title() method of the wpsc_cart_item class consistently throughout cart messages.
Update readme to reflect previous commit.  Previous commit fixes issue #494.  Props @benhuson and @JeffPyeBrook for initial patches.
Minor whitespace changes, minor UX change to coupons to focus on newly generated conditional element.
create purchase log object from purchase log id property, avoids fatal error if global is undefined
remove superfluous references to gloval variables
compare cart item meta in set_item function when determining if the quanitity should be increased
function to comapre cart item meta added
Don't translate deprecated function replacement, as it's code, not words.
Rewrite and privatize _wpsc_get_exchange_rate().  Also makes CURRENCYCONVERTER a simple wrapper for it.  If specific locales find that Google's rates are insufficient for them, the filters in WP_Http will allow for overriding.  Needs lots of testing.
Update readme reflecting Currency Conversion API change.
Fix a few notices in the theme engine.
In current beta, shipping state does not change when changing dropdown.  This is a significant regression.