…ruby#2232)

this no longer makese sense - and leads to confusing behavior when Ruby objects are used within Java (delegating to <=> which might be user-defined)

every-one is expected to handle <=> on 1.9 (and return nil if not comparable)
on 1.8 we still swallow a NoMethodError as Object does not provide <=>

* jruby-1_7:
  some more comparable asserts including for the Java compareTo part
  native RubySymbol#compareTo since we expect to always be able to sort
  should not-rewrite jump exceptions twice as well (not just raise ones)
  delete un-used imports
  [ji] do not rewrite stack-trace twice for Ruby (raise) exceptions
  base compareTo should not silence all Ruby raised exceptions (fixes #2232)
  re-arrange rescue spec (we're about to spec some more behavior)
  only test nil return from Object cmp on 1.9 (on 1.8.7 its expected to raise)
  more of correct $! restore + use get/setErrorInfo for better predictability
  another incorrect $! with numeric coercion on <=> + cleanup getRuntime()
  Fix some consumers for #1601.  Don't leak out  if we are swallowing the raised exception

Conflicts:
	core/src/main/java/org/jruby/Main.java
	core/src/main/java/org/jruby/RubyBasicObject.java
	core/src/main/java/org/jruby/RubyClass.java
	core/src/main/java/org/jruby/RubyComparable.java
	core/src/main/java/org/jruby/RubyNumeric.java
	core/src/main/java/org/jruby/RubySymbol.java
	core/src/main/java/org/jruby/RubyTime.java
	core/src/main/java/org/jruby/javasupport/JavaCallable.java