Optimize update_addon_download_totals

There was some stale webapp data here overwriting my data. This ignores
webapps and also DELETED addons, plus avoids saving the addon when we
don't need to.
Double escape company for IARC (bug 962362)
Fixes tests broken by 968eede
show spinners when validation results are loading (bug 958219)

close #1658
Add SENTRY_DSN to stage addons settings.
use get/create when marking all notes read
redirect / to /edit on devhub (bug 963407)
Merge pull request #1680 from ngokevin/devurl

redirect / to /edit on devhub (bug 963407)
Merge pull request #1673 from magopian/fix-xunit-bug-jenkins

fix xunit bug on jenkins by updating nose to dev version (bug 963188)
rename EULA to End-User License Agreement