implement serialize / de-serialize for all containers: dump and load from RAM raw memory buffer / through a "reader / writer object"

[jerabaul29]

Following the discussions in issues #661 , #375 , and implementing this in an ad hoc way a couple of time in different projects, I think it would be really nice to have a few "serializer / de-serializer" sets of routines, for each container, to be able to dump a container to a raw memory chunk / restore it from it, taking care of dumping / restoring both the data and all the metadata associated.

Being able to

• i) serialize / deserialize to a RAM raw memory buffer would be great,

and if possible, also being able to

• ii) serialize / deserialize through using a "reader / writer" object as an alternative to directly to RAM could be a nice thing to have too, so that it would be possible to serialize / de serialize directly to for example an external RAM or FRAM bank (though this can be done by serializing / deserializing to RAM first, and then copying back and forth to the external memory bank, so this is not super critical; this workaround would require more RAM though, as an additional "intermediate RAM buffer" would be necessary, which is not a needed per se if serializing deserializing directly with a "reader / writer" object).

[jwellbelove]

I need to revisit my 'persistence' class experiments.