Email service was implemented
Merge remote-tracking branch 'origin/feature/ApplicantsNotification' into feature/ApplicantsNotificationTemo

Conflicts:
	applicants-notification/src/main/java/com/softserveinc/ita/service/impl/MailService.java
	applicants-notification/src/main/resources/META-INF/spring/camel-context.xml
	applicants-notification/src/test/resources/test-email-spring-config.xml
	entity/src/main/java/com/softserveinc/ita/entity/Appointment.java
New tests, separated mocks and impl, queue message is now an entity.