New serealization system

[marty1885]

I'm going to admit. The serialization code Etaler uses stinks. The types are a mess and so do the syntax. First of all, cereal is mediocre but not optimal

• Slow
• Not the smallest binary
• (I think) no runtime error checking
• etc...

An the current code that handles serializing/de-serializing just smells... See the horrible code. So the aim of this issue is to

1. See if we can replace cereal
2. Refactor the serialization code so it don't stink

This properly will cause newer version of Etaler not able to read old save files. But meh..