Fix some Checkstyle issues

- Remove unused imports
- Fix issues relating to line length / whitespace
- Update Checkstyle suppression in matcher classes with new check name

.checkstyle.xml

@@ -149,7 +149,9 @@
             <property name="allowSamelineMultipleAnnotations" value="true"/>
         </module>
         <module name="NonEmptyAtclauseDescription"/>
-        <module name="JavadocTagContinuationIndentation"/>
+        <module name="JavadocTagContinuationIndentation">
+            <property name="offset" value="2"/>
+        </module>
         <module name="AtclauseOrder">
             <property name="tagOrder" value="@param, @return, @throws, @deprecated"/>
             <property name="target" value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>

src/main/java/fr/xephi/authme/datasource/MySQL.java

@@ -105,7 +105,8 @@ public class MySQL extends AbstractSqlDataSource {
             Class.forName(this.className);
         } catch (ClassNotFoundException e) {
             this.className = DatabaseSettings.MYSQL_DRIVER_CLASS_NAME.getDefaultValue();
-            logger.info("Driver class '" + this.className + "' not found! Falling back to the built-in MySQL driver (" + this.className + ")");
+            logger.info("Driver class '" + this.className + "' not found! Falling back to the built-in MySQL driver ("
+                + this.className + ")");
         }
         this.database = settings.getProperty(DatabaseSettings.MYSQL_DATABASE);
         this.tableName = settings.getProperty(DatabaseSettings.MYSQL_TABLE);

src/main/java/fr/xephi/authme/process/email/AsyncAddEmail.java

@@ -43,7 +43,8 @@ public class AsyncAddEmail implements AsynchronousProcess {
     @Inject
     private BukkitService bukkitService;
 
-    AsyncAddEmail() { }
+    AsyncAddEmail() {
+    }
 
     /**
      * Handles the request to add the given email to the player's account.

src/main/java/fr/xephi/authme/service/AntiBotService.java

@@ -11,8 +11,6 @@ import fr.xephi.authme.util.AtomicIntervalCounter;
 import org.bukkit.scheduler.BukkitTask;
 
 import javax.inject.Inject;
-import java.time.Instant;
-import java.time.temporal.ChronoUnit;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 import static fr.xephi.authme.service.BukkitService.TICKS_PER_MINUTE;

src/main/java/fr/xephi/authme/service/BukkitService.java

@@ -14,9 +14,7 @@ import org.bukkit.command.CommandSender;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.entity.Player;
 import org.bukkit.event.Event;
-import org.bukkit.plugin.Plugin;
 import org.bukkit.scheduler.BukkitRunnable;
-import org.bukkit.scheduler.BukkitScheduler;
 import org.bukkit.scheduler.BukkitTask;
 
 import javax.inject.Inject;

src/main/java/fr/xephi/authme/service/GeoIpService.java

@@ -304,12 +304,12 @@ public class GeoIpService {
      *
      * @param ip textual IP address to lookup
      * @return the wrapped Country model or {@link Optional#empty()} if
-     * <ul>
+     *   <ul>
      *     <li>Database reader isn't initialized</li>
      *     <li>MaxMind has no record about this IP address</li>
      *     <li>IP address is local</li>
      *     <li>Textual representation is not a valid IP address</li>
-     * </ul>
+     *   </ul>
      */
     private Optional<Country> getCountry(String ip) {
         if (ip == null || ip.isEmpty() || !isDataAvailable()) {

src/main/java/fr/xephi/authme/settings/SettingsMigrationService.java

@@ -67,7 +67,8 @@ public class SettingsMigrationService extends PlainMigrationService {
         }
         String driverClass = reader.getString(DatabaseSettings.MYSQL_DRIVER_CLASS_NAME.getPath());
         if ("com.mysql.jdbc.Driver".equals(driverClass) || "com.mysql.cj.jdbc.Driver".equals(driverClass)) {
-            configurationData.setValue(DatabaseSettings.MYSQL_DRIVER_CLASS_NAME, DatabaseSettings.MYSQL_DRIVER_CLASS_NAME.getDefaultValue());
+            configurationData.setValue(DatabaseSettings.MYSQL_DRIVER_CLASS_NAME,
+                DatabaseSettings.MYSQL_DRIVER_CLASS_NAME.getDefaultValue());
             changes = true;
         }
 

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

@@ -11,7 +11,8 @@ import java.util.Objects;
 /**
  * Custom matchers for AuthMe entities.
  */
-@SuppressWarnings("checkstyle:JavadocMethod") // Justification: Javadoc would be huge because of the many parameters
+// Justification: Javadoc would be huge because of the many parameters
+@SuppressWarnings("checkstyle:MissingJavadocMethod")
 public final class AuthMeMatchers {
 
     private AuthMeMatchers() {

src/test/java/fr/xephi/authme/data/limbo/LimboPlayerMatchers.java

@@ -17,7 +17,8 @@ import static org.hamcrest.collection.IsIterableContainingInOrder.contains;
 /**
  * Contains matchers for LimboPlayer.
  */
-@SuppressWarnings("checkstyle:JavadocMethod") // Justification: Javadoc would be huge because of the many parameters
+// Justification: Javadoc would be huge because of the many parameters
+@SuppressWarnings("checkstyle:MissingJavadocMethod")
 public final class LimboPlayerMatchers {
 
     private LimboPlayerMatchers() {