Android Support

[jrobsonchase]

Android is one of the big usecases for Java, and we already have cross-compilation working for it. Unfortunately, it's not quite usable. This is the tracking issue for overall android usability.

• Bad JNI version returned from JNI_OnLoad on Android #54
• Need documentation on cross-compiling for Android #57
• Shared object can't be loaded via the classloader on Android #50
• failed to establish tcp connection on session connect #61
• nix: add rustflags for soname #63