Revert "Added warning if user uses Internet Explorer"

This reverts commit 80cba62f8cd025a263bb00a13fc96ae1c4856aba.
Revert "Revert "Added warning if user uses Internet Explorer""

This reverts commit e37e6dacabba7138f76a0949b5faa0cf10ecb128.
Resaved the pics via GIMP on my Windows-Lap

Now they are nice again.

(Windows is strange...)
Merge branch 'andreas' of https://github.com/mklarmann/EaternityRechner into andreas