Fix for from and reply-to mail headers.

ref: https://github.com/opencart-ce/opencart-ce/commit/d0cc0e553099aa6f0a6f1f78599f9db650d1727d
Klarna Account gateway minimum amount update.
Wrapped PayPal express logging actions in config check to see if debugging is enabled.
Added PayPal Express fix when getting the "The totals of the cart item amounts do not match order amounts".