Revert "Added the sql definition for pages in tl_iso_products. It is required to make the pageTree work"

This reverts commit ada83dfe147347a2e99007ff1da7c3024c25076a.
Separated addToTemplate into multiple methods, downloads are only for orders
Unset model data we don't want to have in arrData
ProductCollection::lock() will set the date column to the lock time
Use collection modification time for price calculation
Use method to check if product collection is locked
tl_iso_product_collection.locked now stores a timestamp

This also tells us when an order has been placed, we don't need
a date field anymore.
CS and deleted outdated field
Throw exception when trying to save a locked product collection
Improved CS, logging and checkout process for several payment methods
Permissions should be available for tl_iso_products
Countries are not required to calculate net tax amount

The included tax is always subtracted for net total
Added method to get shipping and billing address config as array
CS
CS and labels
The price and tax class is now a combined widget if not using advanced prices
Fixed potential exception due to empty product type
Load default tax class for new prices
CS
Use Model to find the fallback