Avoid using select inputs in collaboration forms

[jsperezg]

Collaboration forms should use radio buttons, similar to what have been done to select the collaboration amout for the following inputs:

• Select periodicity
• Select payment method type
• Select existing payment method.

[leio10]

Just to ensure that is clear, payment method type selector and existing payment methods options should be mixed in the same selector, for example:

• existing credit card 1
• existing credit card 2
• existing direct debit
• new direct debit
• new credit card

[jsperezg]

@leio10 For this issue I will integrate only the current functionality. As soon as we start retrieving payment methods for the current user it will appear in the UI as you suggest