Merge fold/map no_break and regular variants

[zilinc]

Issue by ahixon
Thu Apr 9 12:39:44 2015
Originally opened as https://github.csiro.au/ts-filesystems/Cogent/issues/71

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Depends on #175

Once these functions return a factored type, one can just bind the LoopResult variant type to a placeholder. The inner function of course will always return an Iterate type.

Example

Before:

 let (arr, acc) = wordarray_map_no_break[U32, (), ()] #{ .. }

After:

 let ((arr, acc), _) = wordarray_map[U32, (), (), ()] #{ .. }