Do not test java.util.TreeMap's serialization in the Serialize test
Do not test java.util.TreeMap's serialization in the Serialize test

In the Android class path, TreeMap is implemented differently and as a
consequence its serialization is incompatible with OpenJDK's. So let's
test a private static class' serialization instead, to make sure that
the wire protocol defined by the Java Language Specification is
implemented.

This addresses issue #123 reported by Joel Dice.

Signed-off-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>

lwahlmeier/avian,lostdj/avian,ucdseniordesign/avian,ucdseniordesign/avian,bgould/avian,MaartenR/avian,minor-jason/avian,minor-jason/avian,marcinolawski/avian,joshuawarner32/avian,minor-jason/avian,dicej/avian,marcinolawski/avian,bigfatbrowncat/avian-pack.avian,dicej/avian,lostdj/avian,minor-jason/avian,lwahlmeier/avian,bigfatbrowncat/avian-pack.avian,bgould/avian,bgould/avian,lostdj/avian,dicej/avian,marcinolawski/avian,lwahlmeier/avian,bigfatbrowncat/avian-pack.avian,ucdseniordesign/avian,bigfatbrowncat/avian-pack.avian,joshuawarner32/avian,lwahlmeier/avian,MaartenR/avian,MaartenR/avian,bgould/avian,dicej/avian,ucdseniordesign/avian,joshuawarner32/avian,joshuawarner32/avian,lostdj/avian,marcinolawski/avian,MaartenR/avian