Replace CINT by Cling.

documentation/users-guide/ALittleC++.md

documentation/users-guide/AddingaClass.md

documentation/users-guide/FoldersTasks.md

documentation/users-guide/GettingStarted.md

documentation/users-guide/Graphics.md

documentation/users-guide/Introduction.md

documentation/users-guide/MathLibraries.md

documentation/users-guide/Preface.md

documentation/users-guide/PythonRuby.md

documentation/users-guide/ROOTandQt.md

documentation/users-guide/Threads.md

documentation/users-guide/Trees.md

documentation/users-guide/TutorialsandTests.md

documentation/users-guide/WritingGUI.md