lib/standard/ropes: Re-implemented nodes in C using FFI.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: Path is now implemented in pure C

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: stack_to_end implemented in C

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: get_node_from re-implemented in pure C

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: node_at re-implemented in C

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: Hack for typing tests, to be used by C functions.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: Rewrote insert_at in C.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: Rewrote substring in RopeString

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
lib/standard/ropes: Iterator has a native object/list for iterating on a Rope.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>