Use explicit global namespaces in codegen (#1928)

* ipc as a deault feature

* first part of purge

* second part of ns purge

ipc/hypervisor/src/service.rs.in

@@ -17,9 +17,6 @@
 use std::sync::{RwLock,Arc};
 use ipc::IpcConfig;
 use std::collections::HashMap;
-use std::mem;
-use ipc::binary::BinaryConvertError;
-use std::collections::VecDeque;
 
 pub type IpcModuleId = u64;