The Travis post build is only for the main repo

Skip it if it's PR testing or not the main repo
Correct PR testing env variable

Missed that it's not true if it's a PR from the docs
'TRAVIS_PULL_REQUEST: The pull request number if the current job is a
pull request, "false" if it's not a pull request.'
Fixed no-JS support on details/summary polyfill example.
Merge pull request #1024 from nschonni/skip-travis-fetch-not-main-repo

The Travis post build is only for the main repo
Switched the repo variable to a travis environment variable
Fixed jumpiness in loading of GCWU intranet menu bar.
Merge branch 'v3.0' of github.com:wet-boew/wet-boew into v3.0
Merge branch 'v3.0'