Fix several adapter lookups in vocabs and in checkout wizard.

@lukasgraf 

First fix:
![screen shot 2014-07-30 at 15 05 48](https://cloud.githubusercontent.com/assets/437933/3749304/55f43354-17ea-11e4-80cb-42296bc14f34.png)

Admin payment processor is selectable.

Second fix:
![screen shot 2014-07-30 at 15 05 29](https://cloud.githubusercontent.com/assets/437933/3749312/6ca4a566-17ea-11e4-9fc2-f773ffae6a9e.png)

Shows selected payment processor in order confirmation wizard step.