VQkit v1.1 - Charge-density and bonding menu cleanup

Removed option [4] Bonding analysis (COHP / ICOHP interface) from the
Charge density and bonding post-processing menu.

The remaining menu is:
[1] Charge-density difference [VASP/QE]
[2] Bader charge [VASP]
[3] Electron localization function (ELF) [VASP/QE]
[0] Back
[99] Exit VQkit
