Multiple exception bug fixes identified during testing

app/Jobs/EchoareaImport.php

@@ -39,7 +39,7 @@ class EchoareaImport implements ShouldQueue
 	{
 		$this->file = $file;
 		$this->do = $do;
-		$this->prefix = $prefix;
+		$this->prefix = $prefix ?: '';
 		$this->delete_file = $delete_file;
 		$this->delete_recs = $delete_recs;
 	}

app/Jobs/NodelistImport.php

@@ -295,9 +295,13 @@ class NodelistImport implements ShouldQueue
 
 			// We'll search and see if we already have that system
 			} else {
-				$so = System::where('mailer_address',$address)
-					->where('mailer_port',$port)
-					->single();
+				// If we dont have $address/port
+				$so = NULL;
+
+				if ($address && $port)
+					$so = System::where('mailer_address',$address)
+						->where('mailer_port',$port)
+						->single();
 
 				if (! $so)
 					$so = System::where('name',$system)