Change message verification task to add todo comments in same order

- Make verification task add todo comments to YML files in the same order as the MessageKey enum
- Use DefaultCharsets everywhere instead of Guava's Charsets class (thanks to DNx5)

src/test/java/fr/xephi/authme/ConsoleLoggerTest.java

@@ -1,6 +1,5 @@
 package fr.xephi.authme;
 
-import com.google.common.base.Charsets;
 import fr.xephi.authme.output.LogLevel;
 import fr.xephi.authme.settings.Settings;
 import fr.xephi.authme.settings.properties.PluginSettings;
@@ -18,6 +17,7 @@ import org.mockito.runners.MockitoJUnitRunner;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.List;
 import java.util.logging.Logger;
@@ -91,7 +91,7 @@ public class ConsoleLoggerTest {
         // then
         verify(logger, times(2)).info(anyString());
         verifyNoMoreInteractions(logger);
-        List<String> loggedLines = Files.readAllLines(logFile.toPath(), Charsets.UTF_8);
+        List<String> loggedLines = Files.readAllLines(logFile.toPath(), StandardCharsets.UTF_8);
         assertThat(loggedLines, hasSize(2));
         assertThat(loggedLines.get(0), containsString("[FINE] Logging a FINE message"));
         assertThat(loggedLines.get(1), containsString("[INFO] This is an INFO message"));
@@ -129,7 +129,7 @@ public class ConsoleLoggerTest {
         verify(logger).info("Info text");
         verify(logger).warning("Exception occurred: [IllegalStateException]: Test exception message");
         verifyNoMoreInteractions(logger);
-        List<String> loggedLines = Files.readAllLines(logFile.toPath(), Charsets.UTF_8);
+        List<String> loggedLines = Files.readAllLines(logFile.toPath(), StandardCharsets.UTF_8);
         assertThat(loggedLines.size(), greaterThan(3));
         assertThat(loggedLines.get(0), containsString("[INFO] Info text"));
         assertThat(loggedLines.get(1),