Adding `$GOPATH/bin` to `$PATH` in build script.
Adding `$GOPATH/bin` to `$PATH` in build script.

Prevents the need to call `$GOPATH/bin/<command>`, which doesn't work
for users with multiple paths in their `$GOPATH`.

Forestmb/power-league,Forestmb/power-league,Forestmb/power-league,Forestmb/power-league