Shuffle around the wiggle crates (#1414)

* Shuffle around the wiggle crates

This commit reorganizes the wiggle crates slightly by performing the
following transforms:

* The `crates/wiggle` crate, previously named `wiggle`, was moved to
  `crates/wiggle/crates/macro` and is renamed to `wiggle-macro`.

* The `crates/wiggle/crates/runtime` crate, previously named
  `wiggle-runtime`, was moved to `crates/wiggle` and is renamed to
  `wiggle`.

* The new `wiggle` crate depends on `wiggle-macro` and reexports the macro.

The goal here is that consumers only deal with the `wiggle` crate
itself. No more crates depend on `wiggle-runtime` and all dependencies
are entirely on just the `wiggle` crate.

* Remove the `crates/wiggle/crates` directory

Move everything into `crates/wiggle` directly, like `wasi-common`

* Add wiggle-macro to test-all script

* Fixup a test

crates/wasi-common/src/path.rs

@@ -4,7 +4,7 @@ use crate::wasi::{types, Errno, Result};
 use crate::{entry::Descriptor, entry::Entry};
 use std::path::{Component, Path};
 use std::str;
-use wiggle_runtime::{GuestBorrows, GuestPtr};
+use wiggle::{GuestBorrows, GuestPtr};
 
 pub(crate) use sys::path::*;
 

crates/wasi-common/src/snapshots/wasi_snapshot_preview1.rs

@@ -9,7 +9,7 @@ use std::cell::Ref;
 use std::convert::TryInto;
 use std::fs::File;
 use std::io::{self, Read, Seek, SeekFrom, Write};
-use wiggle_runtime::{GuestBorrows, GuestPtr};
+use wiggle::{GuestBorrows, GuestPtr};
 
 impl<'a> WasiSnapshotPreview1 for WasiCtx {
     fn args_get<'b>(

crates/wasi-common/src/wasi.rs

@@ -11,23 +11,23 @@ wiggle::from_witx!({
 pub use types::Errno;
 pub type Result<T> = std::result::Result<T, Errno>;
 
-impl<'a> wiggle_runtime::GuestErrorType<'a> for Errno {
+impl<'a> wiggle::GuestErrorType<'a> for Errno {
     type Context = WasiCtx;
 
     fn success() -> Self {
         Self::Success
     }
 
-    fn from_error(e: wiggle_runtime::GuestError, _ctx: &Self::Context) -> Self {
+    fn from_error(e: wiggle::GuestError, _ctx: &Self::Context) -> Self {
         eprintln!("Guest error: {:?}", e);
         // TODO proper error mapping
         Self::Inval
     }
 }
 
-impl From<wiggle_runtime::GuestError> for Errno {
-    fn from(err: wiggle_runtime::GuestError) -> Self {
-        use wiggle_runtime::GuestError::*;
+impl From<wiggle::GuestError> for Errno {
+    fn from(err: wiggle::GuestError) -> Self {
+        use wiggle::GuestError::*;
         match err {
             InvalidFlagValue { .. } => Self::Inval,
             InvalidEnumValue { .. } => Self::Inval,
@@ -83,7 +83,7 @@ pub(crate) trait AsBytes {
 impl AsBytes for types::Dirent {
     fn as_bytes(&self) -> Result<Vec<u8>> {
         use std::convert::TryInto;
-        use wiggle_runtime::GuestType;
+        use wiggle::GuestType;
 
         assert_eq!(
             Self::guest_size(),