v1.2.3: Exit(0) when -h (--help) option is used.

Due to an upstream change [1], the program will not
exit(0) when the option is used. We need to update
our smoke tests a bit.

[1] golang/go#37533

Exit 0 on -h (--help). Fixes #5

Cf.: golang/go#37533

goreleaser again

goreleaser again

Fix #2: -v -u can be used together

Add 1.14 tests

Update sub.go