macros can be either "simple" macros, which are pike functions, or they can be text strings,
which are treated as templates of the default type, and which receive any arguments passed
in the macro invocation as data in a mapping called "args".
upon startup, string macros are loaded from files contained in the macros directory.
"simple" macros are loaded by scanning the view class for functions with names in the form of
"simple_macro_abc", where abc is the name under which the macro will be registered.
Fins.FinsView