lib/json_serialization: support Arrays

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
nitserial: intro a support tool to deserialize generic types

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: extend test_deserialization with generics

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: test nitserial itself

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: test a module generated by `nitserial`

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