Migrate to java17

[koushikr]

Consider releasing a java17 version of ranger. A lot of clients may still be using the old one, so will continue to maintain it, unless it is a bug that is functional, needn't have to make any improvements onto the old one, Should migrate to 17 and push a new major version from then on. The 2 series maybe.

[santanusinha]

Not possible right now. Will take it up later along with code cleanup to make it properly J17 compliant.