[Csync2] Rename "csync_ssl_cert.pem" back to "csync2_ssl_cert.pem"

[Alexander Seleznev]

Hello, Lars!

You renamed "csync2_ssl_cert.pem" to "csync_ssl_cert.pem" in commit 
5bf2315de4cb836f629cca94e24a43ccbb0518ed.

Can you explain why you did that and fix it if it's possible?

```
 From f6d52928c2502f4dc4837206e060faa67dd9729a Mon Sep 17 00:00:00 2001
From: Alexander Seleznev <a.seleznev at nixys.ru>
Date: Thu, 19 Mar 2015 13:40:39 +0600
Subject: [PATCH] rename csync_ssl_cert.pem to csync2_ssl_cert.pem

---
  conn.c |    2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conn.c b/conn.c
index 2b3611d..5e54693 100644
--- a/conn.c
+++ b/conn.c
@@ -281,7 +281,7 @@ int conn_activate_ssl(int server_role)
          return 0;

      ASPRINTF(&ssl_keyfile, "%s/csync2_ssl_key.pem", systemdir);
-    ASPRINTF(&ssl_certfile, "%s/csync_ssl_cert.pem", systemdir);
+    ASPRINTF(&ssl_certfile, "%s/csync2_ssl_cert.pem", systemdir);

      gnutls_global_init();
      gnutls_global_set_log_function(ssl_log);
-- 
1.7.10.4
```

Best regards,
Alexander Seleznev