modified servlet to use helper methods from BaseServlet
fixed LoadGraphData servlet not to delete JSON from session which caused failure on page reload
backend cleanup
fixed redirect from upload to graph screen to use base app URL
modified RemoveDiagram servlet to use HTTP method DELETE instead of POST
reworked upload screen
moved API servlets to a separate package, made all servlets extend BaseServlet
reworked Register, Login and Logout servlets to work as API
dropped unused servlets
Added remove diagram servlet + minor fixes
LoadGraphData reformat
LoadGraphData user permission check
Added save button
minor fixes
loading of saved diagrams
Created save diagram servlet
Changed diagram table and Diagram class
joined load graph and start visualization steps on uploadFiles page. Removed saving uploaded file to file system.
Vertex/Edge attribute rendering
dropped some unused functionality, merged DefaultPage with UploadFiles servlet
Removed EFP from backend
Removed unnecessarily conversion to string
fixed servlet output encoding
moved backend code to directories following Maven convention