explicitly declare lazy_static dependency

`benches/bench.rs` uses lazy_static but Cargo.toml does not declare a
dependency on it. This causes rustc to use its own internal private
copy instead. Sometimes this causes unintuitive errors like this Debian
bug: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=942243

The underlying issue is https://github.com/rust-lang/rust#27812 but it
can be avoided by explicitly declaring the dependency, which you are
supposed to do anyways.

Closes #1435

Author: infinity0

Cargo.lock

@@ -27,6 +27,7 @@ regex = "1.1.5"
 
 [dev-dependencies]
 glob = "0.3.0"
+lazy_static = "1"
 
 [features]
 simd-accel = []