Adds rewrite rules for skbug.com and adjusts the path of nginx access logs.

BUG=skia:

Review URL: https://codereview.chromium.org/823613002
Add certpoller.

An application to keep certs up to date with their source of truth, which is stored in GCE project level metadata.

BUG=skia:

Review URL: https://codereview.chromium.org/817303002
Fixed regex

BUG=skia:
TBR=jcgregorio

Review URL: https://codereview.chromium.org/813653005