Use py5/jpype to check/set JAVA_HOME

[tabreturn]

"py5 can check if JAVA_HOME exists, and if not, see what jpype.getDefaultJVMPath() returns? If that is not version >= 17, jpype will not be able to start py5. Instead of failing, check in the location where the Python JDK library puts the installs. If Java 17 is found there, py5 can direct jpype to that location. If it isn't found, display a suitable error message."

Call jpype.getDefaultJVMPath() so it isn't necessary to set JAVA_HOME?