Add payment transaction table
Fix JSON error handling for certain exceptions

Not all exceptions have a json-serializable __dict__
Expose format_currency and |markdown in jinja tpls
Let users select a payment method
Make the payment form JS more flexible
Don't show select box if only one payment method
Add registration form info to reg details page
Improve i-box and registration styles

* Remove unnecessary rules
* Polish i-box-buttons
* Add .icon-next-after
Improve registration page

- Add buttons to perform all actions
- Add i-box around basic registration details
Clarify .message-message-box
Improve display of registration details
Add post-registration data
Display register button after deadline
Handle registrants with unknown registration date
Redirect to main registration page on registration
Remove old menu items
Show different body title name
Improve css for payment condition text and action
Move payment conditions to template and polish up
Add visual feedback for payment done/pending