Updated descriptions for Mac OS

[mortang2410]

Cargo does not successfully build on current Mac OS (Ventura 13.0).
I have found the workaround:

• Here is my Cargo.toml (remember to remove the .txt in the filename). In particular rug and gmp-mpfr-sys need to have updated versions to build successfully.

Usage hint:

• Once cargo build --release finishes, in the git repo folder (where Cargo.toml lives), remember to mkdir output (otherwise program will panic and quit) and then try running ./target/release/main -o default.toml locations/flake.toml

Cargo.toml.txt