More robust version definition and use scijava maven repo instead of imagej.
0.3.4
- Use `scyjava` instead of `jrun`.
0.3.3
- fix jnius requirement in setup.py - add version to imglyb_config so it can be checked without importing imglyb - Use `jrun` instead of `jrun.jrun` - do not fail if JVM is already running but emit warning instead - fix classpath issue