Formatting changes only, ahead of JSR-233 fix.
Fix #2090 (also #1494) on behaviour of long in the JSR-223 engine.

java.lang.BigInteger is recognised by the classic object adapter as
adaptable to PyLong. Scopes in the JSR-223 script engine, which strip
the PyLong wrapper, to share a BigInteger with Java, now restore the
PyLong wrapper when Jython accesses them.