Version 2.1.1: libzip/zlib update and bug fixes
Version 2.1.1 fixes bugs:
- updates libzip to v1.7.3.1 and zlib to v 1.2.11.
- only marks the secure content extension as
requiredif it is really required according to the specification. - resolves a security issue (double free / use after free) in the usage of of libzip (https://talosintelligence.com/vulnerability_reports/TALOS-2020-1226)