Macros.
* t/macros/ -- unSKIP and more tests
* Pugs.Eval.Var -- New module containing findVar & co.
* Pugs.Prim.Param -- New module containing foldParam
* Pugs.Prim, Pugs.AST.Internals, Pugs.Eval, Pugs.Prim.List --
Moved several functions to new Pugs.Eval.Var, Pugs.Prim.Param, and
Pugs.Prim.List.
* Pugs.Parser -- Various calls to new fun possiblyApplyMacro.
* Pugs.Parser.Unsafe -- New fun possiblyApplyMacro.
