Changed dim_vec test parameters to use json array

The test generator scripts are updated to iterate over the json
array, but still prefer the language override.

Change-Id: Ie3e369c47d042d0e29ec57cffbf2c43264f7a1ed
adding missing iostream header

Change-Id: Ieed2d759672b8170d53b97fcddaa947acdad0565
Merge topic 'SIMPLEITK-447_AddProcessObjectBase' into next

2428480 adding missing iostream header
Merge topic 'SIMPLEITK-440_AddScalarSetFordim_vec' into next

73c54ad Changed dim_vec test parameters to use json array