Add snapshot functionality for offline inspections
Add snapshot functionality for offline inspections

When trying to debug memory issues it is not always possible to do
so on the target system. Snapshots in recon_alloc allows the user to
easily save a memory snapshot on the target node and then later analyze
it on some other machine.

The names of the functions in the API (i.e. snapshot_Action) was chosen in
order for the functions to be grouped in the documentation and not clutter
it.

See the documentation in snapshot_load/1 for an example use-case.

dch/recon,linearregression/recon,JoshuaJiangFD/recon,imdeps/recon,paulgray/recon,garazdawi/recon,nimishzynga/recon,beni55/recon,velimir0xff/recon,devDroidhang/recon