lib: java is a group

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
java: move `android::java_io` to `java::io` & remove refs to android

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
android: update users of `java::io`

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>