Update gofiles package to use modules (#23)

Remove top-level go.mod file (#21)

Remove top-level go.mod file (#21)

Remove top-level go.mod file (#21)

Update gofiles module dependency (#18)

Update module dependency for errorstringer (#17)

Update dirs module dependency (#16)

Update module dependencies (#15)

Add dependency on github.com/nmiyake/pkg module to prevent
cyclic dependencies for consumers.

Add top-level main.go file (#14)

Update module dependencies (#15)

Add dependency on github.com/nmiyake/pkg module to prevent
cyclic dependencies for consumers.