feat(packets): accept ReadOnlySpan inside of PaketStringEnumerator

feat(packets): add support for multiple separators after a field

feat(packets): add possibility to increment read tokens for arrays using capture and increment read tokens

feat(packets): add PerparedLevel to PacketStringEnumerator's levels to allow multiple prepared levels for nested packets

feat: split packets definitions into separate assembly

Merge pull request #14 from Rutherther/packets-span

Rewrite packets string enumerator to use spans, add Injector for .NET 5+

feat: use ReadOnlySpan for deserialization instead of strings

Merge pull request #12 from Rutherther/packets

Implement custom packet serializer

feat: add support for optional parameters

fix: set enumerator level ReachedEnd to null if not known

feat: do not remove prepared level on pop level

feat: add base packet types converting