4. Upgrading from Minivend 3 to Minivend 4

There were big changes from Minivend 3 to Minivend 4, some of which were incompatible.

Many things were removed as redundant, deprecated, or just plain crufty:

Nested [loop]s

All frame features removed

Tags removed

Directives removed

Minor operations removed

Search lists

Search conditionals

Form data updates

Checkout changes

[if-field] etc.

[search-list]

Global subs