Doc: use standard wording in \brief commands

QDoc does some magic with the \class and \namespaces
and \brief commands, so the following wording must be used:
"The xxx class yyy ..."

Change-Id: Id231f30e8464898b776888d5423523de404aae34
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/plugins/vcsbase/submiteditorwidget.cpp

@@ -50,7 +50,8 @@ enum { defaultLineWidth = 72 };
 /*!
     \class VcsBase::SubmitEditorWidget
 
-    \brief Presents a VCS commit message in a text editor and a
+    \brief The SubmitEditorWidget class presents a VCS commit message in a text
+    editor and a
      checkable list of modified files in a list window.
 
     The user can delete files from the list by unchecking them or diff the selection