gradle build jarWithLib seems not work

[hrh007]

./gradlew build ; I just cannot build a jar with lib so or dylib , in osx or linux env;

[hrh007]

@jimexist @yjshen maybe I am wrong; can you renew readme and guide how to build jarwithlib; thanks
I have build lib in datafusion-jni use cargo build; but the jar donnot cotains lib

[hrh007]

I mkdir ${root_dir}/datafusion-java/build/jni_libs/osx-x86_64[linux-x86_64], and copy lib to the dir, It works;

[jimexist]

I mkdir ${root_dir}/datafusion-java/build/jni_libs/osx-x86_64[linux-x86_64], and copy lib to the dir, It works;

can you directly create a PR to change the README? thanks