GolangCI complained:
testArray is unused (from deadcode)
But this function was actually wrong being a copy-paste of testMakeStackMap(),
it also didn't conform to testMake... naming scheme, so this fixes it. To make
thing more uniform NewArray() was also changed to return error, map_test.go
code adjusted to this changes and finally array_test.go was added as a stub
for future Array testing.
