io API

[radumarias]

Implement a similar API to tokio::io that calls methods from EncryptedFs.

Structure of crypto module

• crypto::io

Flow

• Use crypto::fs::OpenOptionsto create a crypto::fs::File from https://github.com/radumarias/rencfs/issues/97
• That calls EncryptedFs::open with corresponding read, write flags and internally we keep the CryptoReaderSeek or/and CryptoWriterSeek based on flags passed to open
• When the File object is dropped we close the handle with EncryptedFs::release
• You can use crypto::io to read of write to the File.

[radumarias]

Moved to https://github.com/radumarias/rencfs/issues/97