`kitware_logo_footer.png` is too low resolution, and blurry looking

[seanm]

kitware_logo_footer.png is 3 kB and 101 x 26 pixels. At the scaling factor I use in my web browser, it looks noticeably blurry. I don't even have a HiDPI monitor either.

Contrast with cdash.png at 19 kB and 270 x 270 pixels, which looks quite nice.

[seanm]

Actually, this is a regression vs cdash 2.6, which has a bigger kitware_logo.png at 1421 x 365 pixels.