stdlib/ropes: Prepping ropes to be compatible when Strings are detached from Collection.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
stdlib/strings: Changed test_isa to be compatible later on when Strings are independant from Collection.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
stdlib/strings: Detached Strings from the Collection block.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
stdlib/strings: Cleaned the old way of defining private attributes (readable var _...) and replaced with normal vars.

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