Release version 2.1.6

Merge branch 'release-2.1.6' into main

Release version 2.1.5

New features are:

• integrated external documentation from MassBank-documentation
• Validator checks serialization: record file -> internal representation -> (database) -> record file

Release version 2.1.4

Release version 2.1.4

Release hotfix version 2.1.3.1

Release hotfix version 2.1.3.1

Release version 2.1.3

Merge pull request #233 from MassBank/release-2.1.3

Release version 2.1.3

Release version 2.1.2

Merge branch 'hotfix-2.1.2'