Modify proxyiv syntax #180
Description
Modify proxyiv syntax to avoid clashes with variables. If a variable is named "select", then we don't know if the user meant to use "select" as the iv or if they want the proxy to be automatically selected.
Syntax should be proxyiv(select) or proxyiv(variables varlist) or proxyiv(leads numlist)
We'll change this slowly as not to make this problematic to users. First deprecate, then defunct, then remove.