Update checkstyle config and CodeClimate exclusions

- Add new checkstyle checks: require Javadoc on large private methods, default in switch, declaration order & others
- Update path exclusions in CodeClimate config to match newly renamed classes (e.g. PHPBB -> PhpBB)
  - Create consistency check testing that excluded paths exist as classes
- Fix some trivial violations

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

@@ -0,0 +1,51 @@
+package fr.xephi.authme;
+
+import fr.xephi.authme.util.Utils;
+import org.bukkit.configuration.file.FileConfiguration;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.junit.Test;
+
+import java.io.File;
+import java.util.List;
+
+import static org.hamcrest.Matchers.empty;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.not;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Consistency test for the CodeClimate configuration file.
+ */
+public class CodeClimateConfigTest {
+
+    private static final String CONFIG_FILE = ".codeclimate.yml";
+
+    @Test
+    public void shouldHaveExistingClassesInExclusions() {
+        // given
+        FileConfiguration configuration = YamlConfiguration.loadConfiguration(new File(CONFIG_FILE));
+        List<String> excludePaths = configuration.getStringList("exclude_paths");
+
+        // when / then
+        assertThat(excludePaths, not(empty()));
+        for (String path : excludePaths) {
+            String className = convertPathToQualifiedClassName(path);
+            assertThat("No class corresponds to excluded path '" + path + "'",
+                Utils.isClassLoaded(className), equalTo(true));
+        }
+    }
+
+    private static String convertPathToQualifiedClassName(String path) {
+        // Note ljacqu 20170323: In the future, we could have legitimate exclusions that don't fulfill these checks,
+        // in which case this test needs to be adapted accordingly.
+        if (!path.startsWith(TestHelper.SOURCES_FOLDER)) {
+            throw new IllegalArgumentException("Unexpected path '" + path + "': expected to start with sources folder");
+        } else if (!path.endsWith(".java")) {
+            throw new IllegalArgumentException("Expected path '" + path + "' to end with '.java'");
+        }
+
+        return path.substring(0, path.length() - ".java".length()) // strip ending .java
+            .substring(TestHelper.SOURCES_FOLDER.length())         // strip starting src/main/java
+            .replace('/', '.');                                    // replace '/' to '.'
+    }
+}