At this point all we're doing is turning on warnings, strict, and 5.10 features by default in all files. This also defines a $Koha::VERSION variable which is going to be the basis for the code revision number, as opposed to $C4::Context::VERSION, which is the data config version number.
Marking a subscription serial as "arrived" will now redirect the user to the item editing screen for them to save the barcode if an item is created for the sub-ser. Also, the items.holdingbranch and items.homebranch fields will be set to the subscriptions.branchcode value by default.
Adds permissions to constrain CRUD operations on periodicals and periodical_serials.