add login/logout for user:user
add info about BAD Credentials when login failed
add login through Who
Merge branch 'master' of https://github.com/tumofeu/Tree-Visualisation

Conflicts:
	trees/WebContent/WEB-INF/spring/context.xml
	trees/WebContent/WEB-INF/views/index.jsp
	trees/src/main/java/com/epam/hackathon/trees/web/controller/LoginController.java
Merge branch 'master' of https://github.com/tumofeu/Tree-Visualisation

Conflicts:
	trees/WebContent/WEB-INF/views/index.jsp