implements higher-order inline iterators and return type inference for iterators
implicit auto return type for inline iterators
fix #966

test for ``map`` defined as inline iterator
Merge branch 'devel' of github.com:Araq/Nimrod into devel
few more fixes for static params in macros; new failing test cases for static evaluation
Merge branch 'devel' of github.com:Araq/Nimrod into devel