added main view and presenter classes, re #12610

Code/Mantid/MantidQt/CustomInterfaces/CMakeLists.txt

...stomInterfaces/EnggDiffraction/EnggDiffractionPresenter.h

...tCustomInterfaces/EnggDiffraction/EnggDiffractionQtGUI.ui

...omInterfaces/EnggDiffraction/EnggDiffractionQtTabCalib.ui

...nterfaces/EnggDiffraction/EnggDiffractionQtTabSettings.ui

...stomInterfaces/EnggDiffraction/EnggDiffractionViewQtGUI.h

...tomInterfaces/EnggDiffraction/IEnggDiffractionPresenter.h

...QtCustomInterfaces/EnggDiffraction/IEnggDiffractionView.h