v5.7.1

This patch fixes:

• erroneous release date
• issues in the FindMMG.cmake files (provided to help library users to find Mmg)
• a wrong installation path

What's Changed

• [CMake] Correct release date in CMake by @loumalouomega in #193
• [CMake] Correcting last versions of CMake modules by @loumalouomega in #194

Full Changelog: v5.7.0...v5.7.1