BZ1032308 Warn if node address not found in rhq-storage-auth.conf

Warnings added, will stop after 5 times.

Fixed possible file descriptor leak.

Added a test to test the class and warning output.
        BufferedReader reader = null;
        try {
            addresses.clear();
            reader = new BufferedReader(new FileReader(authConfFile));
            String line = reader.readLine();

            while (line != null) {
                addresses.add(InetAddress.getByName(line));
                line = reader.readLine();
            }
        } catch (IOException e) {
            throw new RuntimeException("Failed to load addresses from " + authConfFile, e);
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    throw new RuntimeException("Failed to close authentication config file " + authConfFile, e);
                }
            }
            // or just IOUtils.closeQuietly(reader); instead the insanity above if Apache Commons are on classpath
        }

would be even better