Adjusting builtin methods to complete them and make them available on Shoes

As #892 and #891 the builtin methods have to be available on the `Shoes` class itself and a couple of color methods are also builtin.

This also adds `color` and `pattern` in addition to what shoes3 had, but I think they are good additions :-)

The only original method that we don't support now is `exit` for which I'll create a separate issue.

Reviews plase, but most of the changes are rather easy.