make it static link

[呼啸随风]

now, this release exec need glibc.
I want to use it in alpine linux, which use musl instead of glibc. It doesn't work unless build from source.

so, I think we can add ldflags to go build, and make it static link the libc.

I create a pr #159 .

[Miao Wang]

I suggest that a musl version can be built along with the glibc version if you really in need of that.

[呼啸随风]

@shankerwangmiao

Yes, Build two binary can cover my case.