QTMOBILITY-1475 Document addition maps mem cache usage.
QTMOBILITY-1475 Document addition maps mem cache usage.

kaltsi/qt-mobility,kaltsi/qt-mobility,enthought/qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,qtproject/qt-mobility,KDE/android-qt-mobility,qtproject/qt-mobility,qtproject/qt-mobility,KDE/android-qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,KDE/android-qt-mobility,tmcguire/qt-mobility,enthought/qt-mobility,tmcguire/qt-mobility,kaltsi/qt-mobility,tmcguire/qt-mobility,KDE/android-qt-mobility,qtproject/qt-mobility,kaltsi/qt-mobility,enthought/qt-mobility,kaltsi/qt-mobility,tmcguire/qt-mobility,tmcguire/qt-mobility,kaltsi/qt-mobility,enthought/qt-mobility