All associative array properties now work as they should.
Fixed problems with some cases of array.length and array.ptr.
Fixed some problems with array properties.
Fixed 'in' contracts.
Fixed some problems with the string runtime support functions.
Fixed initialization of array of structs.
Fixed slice assignment where LHS is slice but RHS is dynamic array.
Fixed problems with result of assignment expressions.
Fixed foreach problems with key type mismatches.
