changing syntax of member functions

i'm going to change the syntax of member functions.

they're currently associated by being in the same module, but i think the way golang does it is simpler.

current style:

```C

struct Foo {}

fn foo(Foo *self, int bla) {}

```


new style:

```C

struct Foo {}

fn(Foo *self) foo (int bla) {}

```


this might also fix https://github.com/zetzit/zz/issues/123