Exclude external JavaScript libraries from beeing validated in Eclipse 4

Due to an Eclipse Bug, JavaScript errors of external JavaScript libraries are marked as erroronous showing the red failure marker even if JavaScript errors are excluded from the contents Markers view, see https://bugs.eclipse.org/bugs/show_bug.cgi?id=349020

Workaround as spooted in the Eclipse bug history:

I have found that I can leave the JavaScript Validator enable and ignore 

specific files by adding a suitable exclusion pattern e.g. **/jquery*.js to 

the JavaScript/Include Path/Source/Excluded group 

(Project->Properties->JavaScript->Include Path->Source).