Remove unneeded extern crate, macro_use, and tidy uses.

crates/lightbeam/src/lib.rs

@@ -1,19 +1,6 @@
 #![cfg_attr(test, feature(test))]
 #![feature(proc_macro_hygiene)]
 
-#[macro_use]
-extern crate smallvec;
-extern crate capstone;
-extern crate either;
-pub extern crate wasmparser;
-#[macro_use]
-extern crate memoffset;
-extern crate dynasm;
-extern crate dynasmrt;
-extern crate itertools;
-// Just so we can implement `Signature` for `cranelift_codegen::ir::Signature`
-extern crate cranelift_codegen;
-extern crate multi_mut;
 #[cfg(test)]
 extern crate test;
 

crates/lightbeam/src/microwasm.rs

@@ -1,5 +1,5 @@
 use crate::module::{ModuleContext, SigType, Signature};
-use smallvec::SmallVec;
+use smallvec::{smallvec, SmallVec};
 use std::{
     convert::TryInto,
     fmt,

crates/lightbeam/src/module.rs

@@ -7,6 +7,7 @@ use cranelift_codegen::{
     ir::{self, AbiParam, Signature as CraneliftSignature},
     isa,
 };
+use memoffset::offset_of;
 use more_asserts::assert_le;
 use wasmparser::{FuncType, MemoryType, ModuleReader, SectionCode, Type};