Merge pull request #386 from vlopes11/ssz-ambiguous

`ssz` is ambiguous (name vs any other name during import resolution)

eth2/utils/ssz/src/macros.rs

@@ -50,8 +50,8 @@ macro_rules! impl_decode_via_from {
 
 #[cfg(test)]
 mod tests {
+    use self::ssz::{Decode, Encode};
     use crate as ssz;
-    use ssz::{Decode, Encode};
 
     #[derive(PartialEq, Debug, Clone, Copy)]
     struct Wrapper(u64);