Remove Array#flatten; Remove Array#find_all_indices

Core gems provide Array#flatten now.
Array#find_all_indices not used in this code base
Remove unused code

Removed left over code from the automagic overlayer
Remove unused code

Remove left over overlay automagic code
Remove unused code

Removed left over overlayer automagic code
Remove unused code
Remove unused code
fix function call via library
add x86_64 linux
reformatting
match MRI: allow an enum to be specified as return type

returns symbol for enum member represented by integer value
matches MRI FFI
reformatting
add test for enum as return; add test of :bool
add assertions for booleans
add test function returning enum
test runner update