more things case consistent
added `map` to sets
added tests for set
fixed a bug in `map` for sets
fixes #797; generic procs can be used in places expecting matching concrete proc types
fixes #612
Fixes macros.len crashing on nodes which lack the sons field.
newProc can now be used to construct iterator defs.
moved tsets test to collections/
edited compiler's config
the tester now produces a diff in the JSON
Merge branch 'devel' of https://github.com/Araq/Nimrod into devel
koch install should work now as documented