Add sass assets
Remove grids
Add the ChildBenefitTaxCalculator class and specs
Bootstrap initial calculator form and controller
Move main form to /main and leave landing page alone

Store all params cross request
Add gift_aid_donations field to calculator

Also fix typo in file name. "benefix_tax" -> "benefit_tax"
Add landing page text and tax year parameter
Fix syntax error in lib spec
Add some capybara integration tests for the calculator
Import stylesheets from the prototype that Amy used
Expose tax_year
Add some view helpers to tidy things up

Move HTML for things into view helpers so the structure lives in one
place. Move some things into partials.
Update specs to reflect HTML changes
Integration tests for adding new children
Fix the adjusted_net_income calculation

Add in some of the calculations for calculating the owed amount
Flush out tests and code for calculating the tax owed
output amount owed
Fix simple tax calculations and tests
Add tests for tax year 2013
fix integration tests