hides error message when killing/creating new ajax request. Fixes DEVELOPER-711

Developer materials fix
Merge pull request #291 from wesbos/DEVELOPER-711

Fixes DEVELOPER-711
Update cdn.yml
Fix therubyracer dependency
DEVELOPER-719 fix typo
Update cdn.yml
Update cdn.yml
Update cdn.yml
Update cdn.yml
Merge pull request #296 from pmuir/fix_therubyracer

Fix therubyracer dependency
Update cdn.yml
Update cdn.yml
Update cdn.yml
Blog context, author, and title
Merge pull request #297 from pmuir/DEVELOPER-719

DEVELOPER-719 fix typo
Merge pull request #298 from LightGuard/DEVELOPER-677

Blog context, author, and title
Update cdn.yml
add JBDS 8 Beta2 and relabel Stand-Alone Installer + zips (DEVELOPER-733)
update links to jars and zips using GG URLs from Chris O'Brien ( https://engineering.redhat.com/rt/Ticket/Display.html?id=302857 ) [ DEVELOPER-733 ]
DEVELOPER-733 use Download Manager short URLs