Easier file parsing with integrated formatting

Sample yaml:
```yaml
users:
 - name: Hilario
   access:
    - admin
    - send_mail
 - name: Esteban
   access:
    - send_main
    - dashboard
```

Parse:

```go
totalUsers, _ := config.Count("users")
for uIdx := 0; uIdx < totalUsers; uIdx++ {
  name, _ := config.Get("users[%d].name", uIdx)
  totalAccess, _ := config.Count("users[%d].access")
  for aIdx := 0; aIdx < totalAccess; aIdx++ {
    access, _ := config.Get("users[%d].access[%d]", uIdx, aIdx)
  }
}
```