commenting regex in flat rate shipping
adding new method to calculate percentage rate adjustment for flat rate shipping
correcting cart template class names
Return request relative link headers, fixes #4925

When WordPress is running inside of a sub-directory,
get_woocommerce_api_url() returns the domain along with the
sub-directory path, which results in a duplicate path when the API
request string is added. This commit fixes this by fetching only the
home host and adding the request path to it. set_url_scheme() is used
to set the scheme to either http or https based on the request itself
instead of basing it on whether force_ssl_checkout is enabled or not.
Merge pull request #4938 from BFTrick/cart-variation-classes

Correcting Cart Template Class Names
Merge pull request #4935 from BFTrick/refactor-flat-rate-percentage-calc

Adding Method to Calculate Percentage Rate Adjustment for Flat Rate Shipping
Merge pull request #4932 from BFTrick/flat-rate-costs-regex

Comment RegEx in Flat Rate Shipping
Username from email hook Closes #4941
Combine two meta queries into one #4901