Usync: Barebones Usync Protocol support (#960)

* feature(feature/usync-mex): initial commit

* chore: fix merge commit

* chore:lint

src/index.ts

@@ -7,6 +7,7 @@ export * from './Store'
 export * from './Defaults'
 export * from './WABinary'
 export * from './WAM'
+export * from './WAUSync'
 
 export type WASocket = ReturnType<typeof makeWASocket>
 export { makeWASocket }