Add presentations section and pathops file for test

Add presentations section and pathops file for test

BUG=skia:
NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=1111453002

Committed: https://skia.googlesource.com/skia/+/a6f75070baf5f72604f27aac125c111ea750d725

[hcm, 2015-04-27 18:32:04]

hcm@google.com changed reviewers:
+ caryclark@google.com

[hcm, 2015-04-27 18:36:06]

On 2015/04/27 18:32:04, hcm wrote:
> mailto:hcm@google.com changed reviewers:
> + mailto:caryclark@google.com

Here's a CL with a Presentations section and Path Ops page you can edit with the
rest of your slides after it goes in.. I experimented, speaker notes can be
enabled, slides do not progress unless you choose play vs the arrows to flip.  I
think the smaller size via Publish to Web feels like a better match to our site
elements and to be able to provide a page with many on it.

[caryclark, 2015-04-27 18:41:13]

lgtm

[hcm, 2015-04-27 19:44:26]

The CQ bit was checked by hcm@google.com

[commit-bot: I haz the power, 2015-04-27 19:44:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1111453002/60001

[commit-bot: I haz the power, 2015-04-27 19:44:44]

Committed patchset #4 (id:60001) as
https://skia.googlesource.com/skia/+/a6f75070baf5f72604f27aac125c111ea750d725