Added point of failure link to the builders page

The point of failure is the link to the first stdio or TestReport log found for a failed build

- Added small amount of caching to the build json
- Minor fixes to the build json
- Added a new icon for point of failure and added the config json to the font folder so that it's usable by all on fontello.com
Merge branch 'staging' of https://github.com/Unity-Technologies/buildbot into staging

Conflicts:
	master/buildbot/status/web/files/prod/css/default.css
	master/buildbot/status/web/files/prod/script/main.js
	master/buildbot/status/web/files/prod/script/main.js.map
	master/buildbot/status/web/files/prod/script/project/rtBuilders.js
	master/buildbot/status/web/files/prod/script/project/rtBuilders.js.map
	master/buildbot/status/web/files/prod/script/templates/builders.mustache
	master/buildbot/status/web/files/script/templates/builders.mustache
Merge branch 'staging' of https://github.com/Unity-Technologies/buildbot into staging

Conflicts:
	master/buildbot/status/web/files/prod/script/main.js
	master/buildbot/status/web/files/prod/script/main.js.map
	master/buildbot/status/web/files/prod/script/project/rtBuilders.js
	master/buildbot/status/web/files/prod/script/project/rtBuilders.js.map