New compact format for snapshots

[ohsayan]

We'll need to implement a new format for compressing and storing snapshots since storing a directory, and transmitting it over a network might introduce additional maintenance complexity for sysadmins. We don't want that to happen and instead implement a single-file snapshot format for easy backups.

Tasks:

• Implement new snapshot engine
• Implement new snapshot compression format
• Add tests

[ohsayan]

We'll avoid linking against something like tar (through flate2 for example) due to a lack of customizability and the level of fine grained control that we need. At the same time, linking against a library statically might increase binary sizes or linking dynamically might introduce the infamous "library not found" issue across platforms. For all these reasons, we will implement our own portable format.

[ohsayan]

This is not a very performant way to export/dump data. Hence, we'll proceed to using something optimal: dump the files in the directory like we currently do