Define methods for the Enumerable module
Implement #my_each
Implement #my_each_with_index
Implement #my_select
Implement #my_all?
Implement #my_any?
Implement #my_none?
Implement #my_none?
Implement #my_count
Refactor #my_none? to use #my_any?
Implement #my_map
Implement #my_inject and tester method #multiply_els
Take proc as argument instead of block for #my_map