Add class to download history postbox

Makes it easier to hide for stores selling physical products
#2610 - Increment the length ID of the array of variable prices when adding a new price
Add today to stats
Merge pull request #2723 from ghost1227/issue/2722

Add today to stats
Merge pull request #2658 from elliott-stocks/patch-12

Add class to download history postbox
Add classes to export postboxes. #2658
Merge pull request #2703 from easydigitaldownloads/issue/2610

#2610 - Increment the length ID of the array of variable prices when add...
Fixed bug #2727

* Modified IPN validation to compare the IPN currency against the order currency, rather than the base one.
Merge pull request #2728 from daigo75/master

Fixed bug #2727
Spacing
Exclude tests folder from grunt workflow
Merge pull request #2729 from chriscct7/master

Exclude tests folder from grunt workflow
Fix missing offset parameter
Fixing misspelling of  to fix the build
#2720 - Adding .editorconfig file
#2720 - Adding link to plugin list
Merge pull request #2731 from easydigitaldownloads/issue/2720

Adding .editorconfig file
Find the highest key and then +1 that for the new row key. #2610
Add data-key to repeatable row TRs. #2610
Start at 1, not 0. #2610