Commit incorrectly missed Maybe.hpp.
Commit incorrectly missed Maybe.hpp.

Monotone-Parent: 2b2e8009ae66369e8b0d881887c8044f19f819ae
Monotone-Revision: d6c21799382986882ced7aa800d8e37d65f4d193

FrancisRussell/desola,FrancisRussell/desola,FrancisRussell/desola