checkLanguageKeys: Fixed accidental ReferenceError introduced in 9231246
checkLanguageKeys & buildProduction: Warn separately about keys missing keys that have been flagged for translation.
checkLanguageKeys: Don't exclude JavaScriptInclude relations when populating the graph.
buildProduction: Quote a string with single quotes instead of doublequotes.
Improved checkLanguageKeys and made it share more code with buildProduction.

Changed the language key sanity checks to no longer piggyback on cloneForEachLocale.

bin/*: Moved the code that sets up event handlers into a transform and use it in all scripts.
makeBabelJob: Run the checkLanguageKeys transform.
checkLanguageKeys: Added the ability to ignore specific warnings and use it in makeBabelJob so that it doesn't issue warnings about the keys that are about to be added to the translation job.
logEvents, stopOnWarning: Let the current transform complete before exiting the process.
checkLanguageKeys: Added the ability to selectively "upgrade" certain message types to warning status.
Implemented checkLanguageKeys --removeunused
1.8.39
checkLanguageKeys: Skip unloaded assets.
1.8.40