SONAR-926 move org.sonar.api.resources.Language to project scope

Instantiation strategy is set to BATCH. Languages can't depend on module components.

sonar-batch/src/main/java/org/sonar/batch/scan/ModuleScanContainer.java

 import org.sonar.api.batch.bootstrap.ProjectDefinition;
 import org.sonar.api.batch.rule.CheckFactory;
 import org.sonar.api.platform.ComponentContainer;
-import org.sonar.api.resources.Languages;
 import org.sonar.api.resources.Project;
 import org.sonar.api.scan.filesystem.FileExclusions;
 import org.sonar.batch.DefaultProjectClasspath;
       PhaseExecutor.getPhaseClasses(),
       moduleDefinition.getContainerExtensions(),
 
-      // TODO move outside project, but not possible yet because of dependency of project settings (cf plsql)
-      Languages.class,
-
       // file system
       FileExclusions.class,
       ExclusionFilters.class,

sonar-batch/src/main/java/org/sonar/batch/scan/ProjectScanContainer.java

 import org.sonar.api.batch.bootstrap.ProjectReactor;
 import org.sonar.api.config.Settings;
 import org.sonar.api.platform.ComponentContainer;
+import org.sonar.api.resources.Languages;
 import org.sonar.api.resources.Project;
 import org.sonar.api.scan.filesystem.PathResolver;
 import org.sonar.api.utils.SonarException;
       GraphPersister.class,
 
       // lang
+      Languages.class,
       HighlightableBuilder.class,
       SymbolizableBuilder.class,
 

sonar-plugin-api/src/main/java/org/sonar/api/resources/Language.java

 
 import org.sonar.api.BatchExtension;
 import org.sonar.api.ServerExtension;
+import org.sonar.api.batch.InstantiationStrategy;
 
 /**
  * The extension point to define a new language
  *
  * @since 1.10
  */
+@InstantiationStrategy(InstantiationStrategy.PER_BATCH)
 public interface Language extends BatchExtension, ServerExtension {
 
   /**