bug #213 Force decimal precision on create order (SirDomin)

This PR was merged into the 1.2 branch.

Discussion
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| Q               | A
| --------------- | -----
| Branch?         | 1.2
| Bug fix?        | yes
| New feature?    | no
| Related tickets | fixes #208 & #183


Commits
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0906332 Force decimal precission on create order
a4758dd use paypal amounts as a string