Bump version to 0.3.9 for development.
Bump version to 0.3.9 for development.

Going forward I think I will use the even/odd version scheme to mark
development and stable versions to make minimum version checks easy.
kovacsbalu/coil,tectronics/coil,marineam/coil,tectronics/coil,marineam/coil,kovacsbalu/coil