Retain documentation version when navigating paginated links.

The old code always raised an exception as the variable being checked
was not defined at that point. Now, it checks the variable that one
expects to be set.

pgweb/search/views.py

@@ -290,7 +290,7 @@ def search(request):
 		conn.close()
 		totalhits = int(hits[-1][5])
 		try:
-			if quoted_suburl:
+			if suburl:
 				quoted_suburl = urllib.quote_plus(suburl)
 			else:
 				quoted_suburl = ''