add more JNI bindings

Signed-off-by: Iliyan Malchev <malchev@google.com>
hook up OcrLib.close()

Signed-off-by: Iliyan Malchev <malchev@google.com>
disable SetPageSegMode

Signed-off-by: Iliyan Malchev <malchev@google.com>
save native context in object, not in static variables

Signed-off-by: Iliyan Malchev <malchev@google.com>
add test code and more assertions, as well as simplify the JNI

Signed-off-by: Iliyan Malchev <malchev@google.com>
write all debug data to /sdcard

Signed-off-by: Iliyan Malchev <malchev@google.com>
add ratings file to tessdata

Signed-off-by: Iliyan Malchev <malchev@google.com>
added support for sharding

Signed-off-by: Iliyan Malchev <malchev@google.com>