### Summary
- Fixes usernames not being `Intern`ed
- Reverts methods related to getting accounts from returning `Account` to `IAccount`.
- Makes `IAccount` also `ISerializable`
- Adds `IGenericReader.ReadAccount()` and `IGenericWriter.Write(IAccount)` -> The read method supports the original serialization of username, and using `IAccount.Serial`. The write method only serializes the `Serial`.
- Exposes `ReadStringRaw()` to allow some advanced scenarios.
