update file permissions

set release month

set expected release month

update changelog

fix LICENSE

- the license text is not under zib copyright
- use exact version of https://www.apache.org/licenses/LICENSE-2.0.txt
  (so, e.g., github will recognize the license)

turn comment into comment

update changelog for 7.1.1

- set release month
- mention a change that was triggered by user request

fix license

- remove appendix

Merge branch 'website-cosmetics' into 'bugfix-70'

Website cosmetics

See merge request integer/soplex!454

increase version to 7.0.0.0