Removed some stringtools functions.

OLD:

    stringtools.snake_case_to_lower_camel_case()
    stringtools.snake_case_to_upper_camel_case()
    stringtools.space_delimited_lowercase_to_upper_camel_case()
    stringtools.upper_camel_case_to_snake_case()
    stringtools.upper_camel_case_to_space_delimited_lowercase()

NEW:

    stringotols.to_lower_camel_case()
    stringotols.to_upper_camel_case()
    stringotols.to_snake_case()
    stringotols.to_space_delimited_lowercase()

CHANGE: should be noted in the 2.16 change log.