bind: support slices as method arguments

[phil-mansfield]

The package

package slice_arg

type T struct {
}

func (t T) Slice(s []float64) {
}

fails with

$ go build && gopy bind --lang=py2 .
2015/08/31 10:29:15 work: /var/folders/j0/l297p36x68dfmcrh07jptj200000gn/T/gopy-628775343
# _/private/var/folders/j0/l297p36x68dfmcrh07jptj200000gn/T/gopy-628775343
./slice_arg.go:164: cannot use s (type cgo_type_0x1114782197) as type []float64 in argument to (*slice_arg.T)(unsafe.Pointer(self)).Slice
2015/08/31 10:29:15 error dispatching command: exit status 2

The following two packages both successfully compile:

package slice_arg

type T struct {
}

func Slice(t T, s []float64) {
}

package slice_arg

type T struct {
}

func (t T) Slice(x float64) {                                            
}

[sbinet]

note to self: this interesting "feature" would be fixed by really harmonizing the wrapping of methods and the wrapping of functions.
the refactorization of these 2 wrappings was somehow stopped in the middle.

[corona10]

#129

Now CFFI engine supports this feature. :)

[rcoreilly]

for old version, closing