== Read Certificate
    $ yubico-piv-tool -a read-certificate -s <slot> [ -o <cert.pem> -K <cert file format> ]

=== Description
Returns the certificate stored on a certain slot.

=== Parameters

|===================================
|Parameter          | Required | Optional | Description | Possible values | Default value

|-s, --slot         | X | | What key slot to operate on | 9a, 9c, 9d, 9e, 82, 83, 84, 85, 86, 87, 88, 89,
                                                          8a, 8b, 8c, 8d, 8e, 8f, 90, 91, 92, 93, 94, 95, f9 |
|-o, --output       | | X | Filename to use as output. If left out, output will be printed to Stdout | None or file name | Stdout
|-K, --key-format   | | X | Format of the key/certificate being read/written | PEM, PKCS12, GZIP, DER, SSH | PEM
|===================================

=== Examples

    $ yubico-piv-tool -a read-cert -s 9a
    -----BEGIN CERTIFICATE-----
    MIIBuTCCAWCgAwIBAgIJAMOZXtijzEepMAoGCCqGSM49BAMCMDgxETAPBgNVBAMM
    CHBpdl9hdXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTAe
    Fw0xOTA4MTMwODEwNDVaFw0yMDA4MTIwODEwNDVaMDgxETAPBgNVBAMMCHBpdl9h
    dXRoMQ0wCwYDVQQLDAR0ZXN0MRQwEgYDVQQKDAtleGFtcGxlLmNvbTBZMBMGByqG
    SM49AgEGCCqGSM49AwEHA0IABKPfSKeNY204JiHsSUwDAV8GuYqZOHfJJxrT4E0q
    VWsKdC5zwRc7xvb2YgbMonPW5BfIUi766/VwWN54UsqWVuWjUzBRMB0GA1UdDgQW
    BBR/bpCmGr+ark0VbGX5UvYWy9dM9DAfBgNVHSMEGDAWgBR/bpCmGr+ark0VbGX5
    UvYWy9dM9DAPBgNVHRMBAf8EBTADAQH/MAoGCCqGSM49BAMCA0cAMEQCIHZZe7Xm
    s6y8LKEBqGnbr1cbniHgMrvM1ST6GpL27HuaAiB+UwjI21GxIsd5r2avmwvT5LeZ
    gQBns9KNCIgkwx+/Iw==
    -----END CERTIFICATE-----
