Fix GRAILS-9834: '<g:external> : media="screen, projector" but should be media="screen, projection"'
Merge pull request #530 from nobeans/GRAILS-9834-2.3.x

GRAILS-9834: '<g:external> : media="screen, projector" but should be media="screen, projection"'
Merge branch '2.3.x' into 2.4.x