Lowest and highest price options

This allows price keys not to be ordered like [0,1,2...] but also can be
random ids if needed
Merge pull request #2396 from pderksen/master

Discount field focus & enter key improvements
Add excerpt to EDD_API. Closes #2399
Merge branch 'master' of github.com:easydigitaldownloads/Easy-Digital-Downloads
Round taxes before they go to PayPal
Replace javascript alert with modal
Add download attribute
Load local jQueryUI
Merge pull request #2401 from ghost1227/issue/2393

Add download attribute
Wrong variable name in function edd_format_amount

$found was used instead of $sep_found leading to a wrong calculation of taxes in the cart and other misbehaviour when the total amount included decimals.
Merge pull request #2403 from Diciannove/master

Wrong variable name in function edd_format_amount
Disable http_request_args for EDD extension updates
Set same meta on cart items added manually to a payment, as when normally purchased
fixed a couple of CSS errors
Merge pull request #2408 from sdavis2702/css-errors

fixed a couple of CSS errors
Force country code to uppercase when validating postal code. #2325
Replace regex rule for Canadian zip codes. #2325
Add textarea to modal
Add textarea to modal
Alignment