muparser 2.3.5

Change Notes for Revision 2.3.5

This is a maintainance release.

New Features:

• added a rnd() function

Fixed Compiler Warnings:

• Fix problem with IntelLLVM fast math

Build System:

• fix for #127 minimum required cmake version set to 3.15
• fix for #132 example1 fails to builds on Windows with mingw gcc
• fix for #147 Build failed with MSVC/C++20