Add User Creator, Validator for input Data for RegistrationServlet 
Add error404 page
Change registration servlet and jsp files
Delete builds
registration successed
Add gitignore
Merge remote-tracking branch 'origin/master' into aleg

Conflicts:
	BuyIt/WebApp/WEB-INF/web.xml
	BuyIt/WebApp/jsp/registration.jsp
	
Login Servlet
Delete builds add gitignore
Update UserWebService (authentication), create web-services.properties
Update UserWebService (loginUser)
login
Converted ProductDAO,CategoryDAO,SubCategoryDAO.
Add ProductService,CategoryService,SubCategoryService.
All methods tested.
Merge chemodurov branch with Alegos.
Create category_viewer.jsp, item_preview.jsp and CategoryServlet
Merge remote-tracking branch 'origin/master' into cehmodurov
Update category_viewer.jsp, item_preview.jsp, HomePageServlet, 
CategoryServlet and some DAO's and Services
Create DescriptionDAO and DescriptionService
registration tooltip
tip.js
Logout and changes in navbar
Create CategoryControllerServlet, update CategoryServlet,
SubCategoryService, item_preview.jsp, category_viewer.jsp, web.xml
Merge with aleg
Merge with Aleg