SettingsAccessor: Refactor helper functions for merge/track sticky
SettingsAccessor: Refactor helper functions for merge/track sticky

Instead of a template use a abstract base class.

Change-Id: I92675bf1c19ef60bec22836eda56240c2f2e4c80
Reviewed-by: Daniel Teske <d8a411aec9a206efedb4d45b75fe8d13f1e2b628@digia.com>
Reviewed-by: Tobias Hunger <012f8d714267bccc9d4766fbeace9f175fcc70c4@digia.com>

farseerri/git_code,farseerri/git_code,Distrotech/qtcreator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,xianian/qt-creator,colede/qtcreator,AltarBeastiful/qt-creator,kuba1/qtcreator,colede/qtcreator,danimo/qt-creator,kuba1/qtcreator,colede/qtcreator,AltarBeastiful/qt-creator,kuba1/qtcreator,martyone/sailfish-qtcreator,farseerri/git_code,colede/qtcreator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,kuba1/qtcreator,maui-packages/qt-creator,kuba1/qtcreator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,colede/qtcreator,colede/qtcreator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,maui-packages/qt-creator,AltarBeastiful/qt-creator,danimo/qt-creator,maui-packages/qt-creator,AltarBeastiful/qt-creator,xianian/qt-creator,farseerri/git_code,danimo/qt-creator,farseerri/git_code,darksylinc/qt-creator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,martyone/sailfish-qtcreator,kuba1/qtcreator,Distrotech/qtcreator,maui-packages/qt-creator,martyone/sailfish-qtcreator,maui-packages/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,maui-packages/qt-creator,farseerri/git_code,darksylinc/qt-creator,maui-packages/qt-creator,xianian/qt-creator,darksylinc/qt-creator,darksylinc/qt-creator,AltarBeastiful/qt-creator,AltarBeastiful/qt-creator,darksylinc/qt-creator,kuba1/qtcreator,darksylinc/qt-creator,xianian/qt-creator,danimo/qt-creator,colede/qtcreator,darksylinc/qt-creator,Distrotech/qtcreator,farseerri/git_code,Distrotech/qtcreator,xianian/qt-creator,danimo/qt-creator,darksylinc/qt-creator,danimo/qt-creator,danimo/qt-creator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,amyvmiwei/qt-creator,danimo/qt-creator,kuba1/qtcreator,Distrotech/qtcreator,farseerri/git_code,kuba1/qtcreator,xianian/qt-creator,Distrotech/qtcreator,amyvmiwei/qt-creator