Make method naming more consistent.

* Use id() for methods returning a string used to represent
    some type of object.
  * Use displayName() for strings that are meant to be user
    visible.
  * Quieten some warnings while touching the files anyway.
  * Move Factories to their products in the plugins where that
    was not done before.

Reviewed-by: dt

src/plugins/git/clonewizard.cpp

@@ -55,7 +55,7 @@ QString CloneWizard::description() const
     return tr("Clones a project from a git repository.");
 }
 
-QString CloneWizard::name() const
+QString CloneWizard::displayName() const
 {
     return tr("Git Repository Clone");
 }