Fix memory leak in DestroyTransport.

Transport (and channels) depends on port_allocator, so we need delete
transport before deleting port_allocator.
The order of members in PeerState make default destructor to delete
port_allocator first, that may crash program in some situation.
Merge pull request #45 from kangjianbin/master

Fix memory leak in DestroyTransport.
Add assert to debug threads.
Fix GetStats Bug.

We must call channel->GetStats in work_thread.
Merge pull request #46 from kangjianbin/master

Fix GetStats bug.
Sync accessing of short_uid_map_
Merge pull request #48 from kangjianbin/master

Sync accessing of short_uid_map_
2 byte header tincan-controller message
change to scoped_pointer from raw pointer
Merge pull request #55 from kyuhojeong/header2

2 byte header tincan-controller message
changed constant variable name to google style

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml
Merge pull request #57 from kyuhojeong/google_c_style

Addition of previously omitted constants and coding style change