Android tests

[FakeTruth]

It seems we'll need a proper callback mechanism into Java, so that:
1, we don't require the "read sensitive log data" permission
2, logging works even on weird android versions

Well, it seems FakeTruth is catching some sleep after his yesterday's midnight-oil-burning

As I stated in a commit log, callling Java functions from C++ is only allowed from a Java thread (not native thread). It's possible to call those functions from other threads, but it's messy. Threads need to be attached and detached to the JVM, confusing stuffs...

Also I was at family

Faketruth are you also planning on making it easier to configurate in the android version?

Not specifically for Android. I think the WebAdmin should be used for configuring the server.