Temporarily remove support for interface types (#1292)

* Temporarily remove support for interface types

This commit temporarily removes support for interface types from the
`wasmtime` CLI and removes the `wasmtime-interface-types` crate. An
error is now printed for any input wasm modules that have wasm interface
types sections to indicate that support has been removed and references
to two issues are printed as well:

* #677 - tracking work for re-adding interface types support
* #1271 - rationale for removal and links to other discussions

Closes #1271

* Update the python extension

crates/misc/py/src/function.rs

@@ -5,25 +5,16 @@ use pyo3::exceptions::Exception;
 use pyo3::prelude::*;
 use pyo3::types::{PyAny, PyDict, PyTuple};
 use std::rc::Rc;
-use wasmtime_interface_types::ModuleData;
 
 // TODO support non-export functions
 #[pyclass]
 pub struct Function {
-    pub instance: wasmtime::Instance,
-    pub export_name: String,
-    pub args_types: Vec<wasmtime::ValType>,
-    pub data: Rc<ModuleData>,
+    pub func: wasmtime::Func,
 }
 
 impl Function {
     pub fn func(&self) -> wasmtime::Func {
-        let e = self
-            .instance
-            .get_export(&self.export_name)
-            .expect("named export")
-            .clone();
-        e.func().expect("function export").clone()
+        self.func.clone()
     }
 }
 
@@ -37,11 +28,11 @@ impl Function {
             runtime_args.push(pyobj_to_value(py, item)?);
         }
         let results = self
-            .data
-            .invoke_export(&self.instance, self.export_name.as_str(), &runtime_args)
-            .map_err(crate::err2py)?;
+            .func
+            .call(&runtime_args)
+            .map_err(|e| crate::err2py(e.into()))?;
         let mut py_results = Vec::new();
-        for result in results {
+        for result in results.into_vec() {
             py_results.push(value_to_pyobj(py, result)?);
         }
         if py_results.len() == 1 {