Implementation of Build Redis from scratch series

This is experimental implementation of Build Redis from scratch series i've done for understand how Redis works under the hood.

Addition to the features covered by the article,

this repo supports following commands
- HGETALL
- DEL
- EXPIRE
- TTL
TTL support. For new entries and existing entries.
AOF rewriting. If a certain file size is reached default AOF will be moved to a different file and the default one will be re-created. When reading on startup, all the files will be read and handled in a goroutine.
Config file support, default configs are,

{
    "aof_enabled": true,
    "aof_dir": "./internal/data/",
    "aof_max_size": 1024 // 1MB -> in bytes
}