Try to avoid Reflections construction exception

From OS X:

WARN org.reflections.Reflections - could not create Dir using directory from url file:/System/Library/Java/Extensions/libAppleScriptEngine.jnilib. skipping.
java.lang.RuntimeException: cannot use dir /System/Library/Java/Extensions/libAppleScriptEngine.jnilib
  at org.reflections.vfs.SystemDir.<init>(SystemDir.java:20)
  at org.reflections.vfs.Vfs$DefaultUrlTypes$3.createDir(Vfs.java:237)
  at org.reflections.vfs.Vfs.fromURL(Vfs.java:99)
  at org.reflections.vfs.Vfs.fromURL(Vfs.java:91)
  at org.reflections.Reflections.scan(Reflections.java:231)
  at org.reflections.Reflections.scan(Reflections.java:204)
  at org.reflections.Reflections.<init>(Reflections.java:129)
  at com.thinkaurelius.titan.core.util.ReflectiveConfigOptionLoader.loadAllClassesUnsafe(ReflectiveConfigOptionLoader.java:223)

This commit may fix the problem, but I haven't been able to reproduce
the problem, so I'm not certain.
Merge branch 'titan09' of github.com:thinkaurelius/titan into titan09