Use lazy_static!() for RegExp
There are a couple of location where we could use lazy_static!() https://docs.rs/regex/1.0.5/regex/#example-avoid-compiling-the-same-regex-in-a-loop
There are a couple of location where we could use lazy_static!() https://docs.rs/regex/1.0.5/regex/#example-avoid-compiling-the-same-regex-in-a-loop