Documentation:  move some things around

NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=4750

Change-Id: I0d1bc77a533ede8e0514ff0b680a5aa851051fc6
Reviewed-on: https://skia-review.googlesource.com/4750
Reviewed-by: Heather Miller <hcm@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
1 file changed