[install-guide/F21-rewrite] Adding a screenshot for memtest

[pbokoc]

commit bf396d239386cd40f909e20a502fb4f1c6b18caf
Author: Petr Bokoc <pbokoc at redhat.com>
Date:   Wed Sep 3 19:20:33 2014 +0200

    Adding a screenshot for memtest

 en-US/images/boot/memtest86.png |  Bin 0 -> 48880 bytes
 1 files changed, 0 insertions(+), 0 deletions(-)
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diff --git a/en-US/images/boot/memtest86.png b/en-US/images/boot/memtest86.png
new file mode 100644
index 0000000..782c962
Binary files /dev/null and b/en-US/images/boot/memtest86.png differ