Editing each cell for users
Modified user editing
Added delete functionality
Updated edit functionality
Added creating new user functionality
Added confirmation dialog for user deletion
Optimized UserTable class, added form hiding after submit action
Modified deleteion - added multiply deleteion with confirmation
User add/edit form implemented in separated window with enabling base grid to prevent creation of other windows
Fixed some bugs in popup windows
Fixed checkboxes
Updated row selection (as plugin)
Added filtration to User grid (needed further upgrading to load from db)