Roy/Sid|13|Added API(s) to retrieve course,module,chapter and message

Added version field to CourseDTO,ModuleDTO,ChapterDTO,MessageDTO

Separated out interfaces for Course,Module,Chapter,Message

Megha/Sid/Sharvani |#14| Added API to retrieve and add bookmarks.

Change-Id: Icdefa73f77c4ae4c5f18b66f8ce6d5a5bd8b3719

Conflicts:
	modules/mtraining/src/main/java/org/motechproject/mtraining/constants/MTrainingEventConstants.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/Chapter.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/ChildContentIdentifier.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/ContentIdentifier.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/Course.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/CourseContentIdentifier.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/domain/Module.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/dto/ChapterDto.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/dto/CourseDto.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/dto/MessageDto.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/dto/ModuleDto.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/service/impl/ChapterNodeHandler.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/service/impl/CourseNodeHandler.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/service/impl/CourseServiceImpl.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/service/impl/ModuleNodeHandler.java
	modules/mtraining/src/main/java/org/motechproject/mtraining/service/impl/NodeHandler.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/domain/CourseTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/osgi/CourseBundleIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/repository/AllCoursesIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/AssertCourseContents.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/ChapterServiceIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/CourseServiceIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/MessageServiceIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/ModuleServiceIT.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/ChapterNodeHandlerTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/CourseNodeHandlerTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/CourseServiceImplTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/MessageNodeHandlerTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/ModuleNodeHandlerTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/service/impl/NodeHandlerOrchestratorTest.java
	modules/mtraining/src/test/java/org/motechproject/mtraining/validator/CourseStructureValidatorTest.java