Improve HF response input

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What has been done:

• Change the keywords for HF excitation energies and response properties:
  • In the do section, one now specifies excited state or response to get HF excited states or response properties
  • An hf response section is added (like the cc responsesection), where the type of response is given
  • The tdhf and cphf response solver sections are collected and are called solver hf response
  • The HF excited state solver section is renamed solver hf es

ToDo-list

The boxes below need to be checked before merge review will start

• Testing
  • All tests pass -rcheck flag enabled in setup.py
  • All tests pass -fbatch flag enabled in setup.py
• Versioning
  • Changelog.md is up to date
  • If merge into master: The patch number in parameters.F90 and changelog.md is up to date
• Website (Needs to be done before merge)
  • Updates (if any) to the website have been added
• Compliance with style guide
  • Do's and dont's
  • Documentation style