Crypt-suffix when file name encryption is on

[yeyudoc]

i hope when file name encryption is on ，we add this suffix to make sure the cloud provider can share the file

[kapitainsky]

As per docs:

--crypt-filename-encryption

How to encrypt the filenames.

Properties:

    Config: filename_encryption
    Env Var: RCLONE_CRYPT_FILENAME_ENCRYPTION
    Type: string
    Default: "standard"
    Examples:
        "standard"
            Encrypt the filenames.
            See the docs for the details.
        "obfuscate"
            Very simple filename obfuscation.
        "off"
            Don't encrypt the file names.
            Adds a ".bin", or "suffix" extension only.

--crypt-suffix only applies to unencrypted file names.