added page about linux
refactoring - added url patterns to the core app
refactoring - added url patterns to the core handbook
refactoring - added a only one function to control all python subjects
refactoring - it was used urlresolvers library, to not need use link hardcoded in the test of app core
refactoring - it was used urlresolvers library, to not need use link hardcoded in the test of app handbook