Misplaced tag for v1.1.5

[gjasny]

Hello,

thanks for maintaining and releasing sml. I noticed the commit hash for the v1.1.5 and the commit with the same name on master differ. Also GitHub tells me that https://github.com/boost-ext/sml/tree/v1.1.5 is not part of any branch.

That's not particularly problematic because the code is the same. But maybe you'd like to have a look.

Thanks, Gregor