Merge pull request #1 from woothemes/master

Update
Update form-shipping.php

Add filter to allow needs_shipping() to be overridden, useful if you want to collect a shipping address for virtual products.

Allows a filter to be used as replacement for get_option('woocommerce_require_shipping_address')

Previous suggestion of add_filter('woocommerce_cart_needs_shipping', '__return_true'); is not suitable
Update form-shipping.php
Update class-wc-cart.php
Update class-wc-cart.php
Update class-wc-cart.php
Update form-shipping.php
Update form-shipping.php
Merge pull request #5230 from ChromeOrange/master

show shipping form filter