Ensure that an ExecJS runtime is available for realsies.
Ensure that an ExecJS runtime is available for realsies.

Fixes #1512

chrise86/refinerycms,Eric-Guo/refinerycms,hoopla-software/refinerycms,stefanspicer/refinerycms,LytayTOUCH/refinerycms,bricesanchez/refinerycms,mojarra/myrefinerycms,mabras/refinerycms,johanb/refinerycms,aguzubiaga/refinerycms,gwagener/refinerycms,johanb/refinerycms,kelkoo-services/refinerycms,mlinfoot/refinerycms,mobilityhouse/refinerycms,bryanmtl/g-refinerycms,Retimont/refinerycms,KingLemuel/refinerycms,anitagraham/refinerycms,kelkoo-services/refinerycms,refinery/refinerycms,simi/refinerycms,Retimont/refinerycms,KingLemuel/refinerycms,johanb/refinerycms,Eric-Guo/refinerycms,stefanspicer/refinerycms,LytayTOUCH/refinerycms,mlinfoot/refinerycms,bricesanchez/refinerycms,LytayTOUCH/refinerycms,simi/refinerycms,mkaplan9/refinerycms,Eric-Guo/refinerycms,refinery/refinerycms,mojarra/myrefinerycms,Retimont/refinerycms,louim/refinerycms,simi/refinerycms,mkaplan9/refinerycms,trevornez/refinerycms,mabras/refinerycms,stefanspicer/refinerycms,hoopla-software/refinerycms,chrise86/refinerycms,kappiah/refinerycms,gwagener/refinerycms,KingLemuel/refinerycms,hoopla-software/refinerycms,anitagraham/refinerycms,refinery/refinerycms,louim/refinerycms,SmartMedia/refinerycms-with-custom-icons,kappiah/refinerycms,aguzubiaga/refinerycms,SmartMedia/refinerycms-with-custom-icons,mlinfoot/refinerycms,aguzubiaga/refinerycms,chrise86/refinerycms,trevornez/refinerycms,simi/refinerycms,mobilityhouse/refinerycms,mkaplan9/refinerycms,anitagraham/refinerycms,bryanmtl/g-refinerycms,sideci-sample/sideci-sample-refinerycms,trevornez/refinerycms,mabras/refinerycms,sideci-sample/sideci-sample-refinerycms,kappiah/refinerycms,gwagener/refinerycms