Replace tabs with a space in search::cleanup().

src/search.cpp

@@ -162,7 +162,7 @@ void cleanup_text(string &text)
     }
 
     pos = 0;
-    while ((pos = text.find('\n', pos)) != string::npos)
+    while ((pos = text.find_first_of("\n\t", pos)) != string::npos)
     {
         text.replace(pos, 1, " ");
     }