Version 1.17
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- Adds support for extra fields to be attached to the order.
- Adds new methods to the shipping and orders objects.
- Cleanup the way addresses are handled in the default form.
- Ensure that all input parameters from the billing form are stripped and/or cleaned.

Version 1.18
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WARNING: This is a major upgrade. There may be compatibility problems, primarily with templates. Though no data should be lost.
WARNING: This will in all likelihood be the last release that supports CMSMS 1.x

- Now require PHP 5.4+
- Works with new payment gateway mechanism.
- Supports multiple payment gateways.
- Improve the way declined and other gateway errors are handled.
- Improvements to handle the way locales that do not use . as a decimal separator are handled.
- Add new extra field to orders table and appropriate API changes.
- Add new method to test if a line item with a specified sku is somewhere in the order.
- Modify (some) default templates to output extra fields.
- Add the ability to process extra fields.
- Cleanup address processing in the order creation process.
- Adds setting notes.
- Improvements for handling multiple carts.