Create skeleton SunriseSunsetPlus repository

[caarmen]

• This new repository will have a maven dependency on the core sunrise sunset library for core functions.
• All issues (including closed unimplemented issues) related to non-core features (other heavenly bodies and specific applications like aviation, photography, etc) will be transferred to the new repository
• One of the simple issues will be implemented in the skeleton repository to set out the structure
• Ownership of the new repository will be transferred to any willing developer/maintainer

[caarmen]

Done: https://github.com/caarmen/SunriseSunsetPlus