OS icon is rendered at 16x16, for some reason we store them mostly in 21x21 but there are other sizes as well. We should probably use the correct size everywhere.

app/assets/images/AIX.png:                PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/Altlinux.png:           PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/Archlinux.png:          PNG image data, 24 x 24, 8-bit/color RGBA, non-interlaced
app/assets/images/bullet_toggle_plus.png: PNG image data, 16 x 16, 8-bit grayscale, non-interlaced
app/assets/images/Centos.png:             PNG image data, 21 x 20, 8-bit/color RGBA, non-interlaced
app/assets/images/Coreos.png:             PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Darwin.png:             PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/Debian.png:             PNG image data, 21 x 25, 8-bit colormap, non-interlaced
app/assets/images/edit-hover.png:         PNG image data, 16 x 16, 8-bit colormap, non-interlaced
app/assets/images/edit.png:               PNG image data, 16 x 16, 4-bit colormap, non-interlaced
app/assets/images/Fedora.png:             PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Freebsd.png:            PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Gentoo.png:             PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Junos.png:              PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/login_logo.png:         PNG image data, 266 x 117, 8-bit/color RGBA, non-interlaced
app/assets/images/navbar.png:             PNG image data, 1400 x 60, 8-bit/color RGBA, non-interlaced
app/assets/images/NXOS.png:               PNG image data, 21 x 21, 8-bit colormap, non-interlaced
app/assets/images/OracleLinux.png:        PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/pie_chart_icon.png:     PNG image data, 17 x 17, 8-bit/color RGBA, non-interlaced
app/assets/images/pie_overlay.png:        PNG image data, 117 x 125, 8-bit gray+alpha, non-interlaced
app/assets/images/Puppet.png:             PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/Rancheros.png:          PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Redhat.png:             PNG image data, 21 x 20, 8-bit/color RGBA, non-interlaced
app/assets/images/Scientific.png:         PNG image data, 24 x 24, 8-bit/color RGBA, non-interlaced
app/assets/images/SLC.png:                PNG image data, 24 x 25, 8-bit/color RGBA, non-interlaced
app/assets/images/Solaris.png:            PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/sort_asc_disabled.png:  PNG image data, 19 x 19, 8-bit/color RGBA, non-interlaced
app/assets/images/sort_asc.png:           PNG image data, 19 x 19, 8-bit/color RGBA, non-interlaced
app/assets/images/sort_both.png:          PNG image data, 19 x 19, 8-bit gray+alpha, non-interlaced
app/assets/images/sort_desc_disabled.png: PNG image data, 19 x 19, 8-bit gray+alpha, non-interlaced
app/assets/images/sort_desc.png:          PNG image data, 19 x 19, 8-bit/color RGBA, non-interlaced
app/assets/images/Suse.png:               PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Ubuntu.png:             PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/VRP.png:                PNG image data, 21 x 21, 8-bit/color RGBA, non-interlaced
app/assets/images/Windows.png:            PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced
app/assets/images/Xenserver.png:          PNG image data, 21 x 21, 16-bit/color RGB, non-interlaced