Remove casacade cc

Closes #76

See merge request !24

Resolve "Define best unit for mass: "eV" or "kg""

Closes #27

See merge request AirShowerPhysics/corsika!22

Resolve "Add jenkins/gitlab-ci to git code hosting"

Closes #24

See merge request !17

Resolve "extension of particle properties to include particle lifetimes"

Closes #67

See merge request !21

Resolve "Cascade::Step logic and tracking"

Closes #53

See merge request !20