Allows for $0 options in extracosts.

Makes the Student Extra Costs module work with line item types that have
$0 options.

Adds a extra_costs_done Record to keep track of when a student has
completed the module.

Also adds a reset button for each group of radio buttons on the form.

Resolves Github Issue #1118.
(cherry picked from commit b231260f73e42d6dccac98b03980e5c715b0db23)
Merge pull request #1134 from learning-unlimited/extra-costs-fix-on-stable-feb14

Allows for $0 options in extracosts.
Fixes bug in accounting controller

Transfer.transaction_id is allowed to be blank, but not null. Changes
the default value for transaction_id in submit_payment() from None to
''.

Resolves Github Issue #1100.
Merge pull request #1139 from learning-unlimited/accounting-fix

Backport: Fixes bug in accounting controller
Add deadline to allow students to cancel registration(cherry picked from commit 93d95d279dd5913b8bce66576c232c46259f93d1)
Merge pull request #1162 from learning-unlimited/backport-add-cancel-reg-deadline

Stable14 Backport - Add deadline to allow students to cancel registration
Fixes issue #1056

Moves the code that fixes the "timeblock" field name to before the
field names are used so that it actually works.
Fixes section list admin binder printable to include home phone
Merge pull request #1181 from learning-unlimited/fix-xss-vuln

Fixes XSS vulnerability in rapid approval system
Merge pull request #1192 from learning-unlimited/stable-feb14-backports

Stable feb14 backports
Stanford production site customizations
Adds teacher_acknowledgement_text Tag