Multiple bugs when cart and donate route activated

Hello,

I'm found some few bugs with this module when you activate /cart and /donate route to make donation.

1. Configuration is not correctly shown due to bad named variable.
2. After you choose a donation and continue the checkout, when you get back to edit donation and then continue to the checkout again, the item name in the summary keep previous name adding "single" or "reccuring" label multiple times
3. The "reccuring" option is always available thouth the module commerce_reccuring is not enabled.

I propose a patch to correct these points.