REGTESTS: ssl: Add "set/commit ssl crl-file" test

This file adds tests for the new "set ssl crl-file" and "commit ssl
crl-file" commands which allow the hot update of CRL file through CLI
commands.
diff --git a/reg-tests/ssl/interCA1_crl_empty.pem b/reg-tests/ssl/interCA1_crl_empty.pem
new file mode 100644
index 0000000..ce9e0f4
--- /dev/null
+++ b/reg-tests/ssl/interCA1_crl_empty.pem
@@ -0,0 +1,27 @@
+-----BEGIN X509 CRL-----
+MIIBjDB2MA0GCSqGSIb3DQEBCwUAMEcxCzAJBgNVBAYTAkZSMR0wGwYDVQQKDBRI
+QVByb3h5IFRlY2hub2xvZ2llczEZMBcGA1UEAwwQSW50ZXJtZWRpYXRlIENBMRcN
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+AH08jXjU5Pc3XThatlTvGA==
+-----END X509 CRL-----
+-----BEGIN X509 CRL-----
+MIICgzBtMA0GCSqGSIb3DQEBCwUAMD4xCzAJBgNVBAYTAkZSMR0wGwYDVQQKDBRI
+QVByb3h5IFRlY2hub2xvZ2llczEQMA4GA1UEAwwHUm9vdCBDQRcNMjEwNDIzMTQz
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++AqgiyB7xGWiRa2SZVPn+j6wHWdohar6zw4UIBLS7EIjvb/RAM6SduScIbc9l+0I
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+BCm2lSjFCK0p/mAgK8yiNQFKnCAgsXU=
+-----END X509 CRL-----