run gofmt
remove extra copy(?)

Unsure if this actually copies it, but it seemed pretty unnecessary.
Use local RNG

When you use the top-level functions, you have to wait for mutexes,
since it's written to be threadsafe. To avoid that overhead, you can
instantiate your own RNG. This amounted to 13% speedup on my system.
Merge pull request #2 from treed/master

Some go fixes
Use mwc-random, picky misc basic style stuff, more strictness
Merge pull request #4 from mikeplus64/patch-1

Use mwc-random, picky misc basic style stuff, more strictness
go: slightly more idiomatic go code. slices are already reference-types.
merge wip/go-slices-are-refs