refractoring class names, delivery and coupon option

git-svn-id: https://svn.typo3.org/TYPO3v4/Extensions/t3sixshop/trunk@78822 735d13b6-9817-0410-8766-e36946ffe9aa
SQL corrected

git-svn-id: https://svn.typo3.org/TYPO3v4/Extensions/t3sixshop/trunk@78823 735d13b6-9817-0410-8766-e36946ffe9aa
Coupons, shipping calculation

git-svn-id: https://svn.typo3.org/TYPO3v4/Extensions/t3sixshop/trunk@78824 735d13b6-9817-0410-8766-e36946ffe9aa