Only show the warning dialog if the state of the sidebars has really changed, so the warning dialog is not  shown anymore at startup if a session has disabled sidebars.
Only show the warning dialog if the state of the sidebars has really changed, so the warning dialog is not
 shown anymore at startup if a session has disabled sidebars.

BUG:212218

svn path=/trunk/KDE/kdesdk/kate/; revision=1046420

cmacq2/kate,hlamer/kate,hlamer/kate,DickJ/kate,DickJ/kate,hlamer/kate,jfmcarreira/kate,hlamer/kate,DickJ/kate,hlamer/kate,hlamer/kate,sandsmark/kate,sandsmark/kate,cmacq2/kate,hlamer/kate,cmacq2/kate,hlamer/kate,hlamer/kate,jfmcarreira/kate,sandsmark/kate,hlamer/kate,sandsmark/kate,jfmcarreira/kate,DickJ/kate