require: warn invalid json

[linoleum-js]

closes #1580

[goto-bus-stop]

thanks for picking this up! & sorry for the long wait. would you mind rebasing this?

[Nikerabbit]

This broke our script that transforms a JSON file to JavaScript file because it is checking the transformed output that is no longer JSON:

"$BASEDIR"/node_modules/browserify/bin/cmd.js "$INPUT"/data/data.json -t "$BASEDIR"/scripts/transform.js -o "$DEST"/data.js

SyntaxError: While parsing /[...]/data.json: Unexpected token ( in JSON at position 0
    at JSON.parse (<anonymous>)
    at DestroyableTransform._transform (/home/nike/stuff/mw/jquery.uls/node_modules/browserify/index.js:669:22)
    at DestroyableTransform.Transform._read (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_transform.js:184:10)
    at DestroyableTransform.Transform._write (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_transform.js:172:83)
    at Labeled.Pipeline._write (/home/nike/stuff/mw/jquery.uls/node_modules/stream-splicer/index.js:70:22)
    at doWrite (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_writable.js:428:64)
    at writeOrBuffer (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_writable.js:417:5)
    at Labeled.Writable.write (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_writable.js:334:11)
    at Labeled.ondata (/home/nike/stuff/mw/jquery.uls/node_modules/readable-stream/lib/_stream_readable.js:619:20)
    at Labeled.emit (events.js:198:13)

Is there a better way to do this?