chore($jshint): #890 - Add JSHint

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chore($ajax.requester): #890 - Lint
chore($button): #890 - Lint
chore($dnd): #890 - Lint
chore($exif): #890 - Lint
chore($features): #890 - Lint
chore($handler.base); #890 - Lint
chore($handler.form.api): #890 - Lint
chore($deletefile.ajax.requester): #890 - Lint
chore($handler.xhr.api): #890 - Lint
chore($identify): #890 - Lint
chore($iframe.xss.response): #890 - Lint
chore($image): #890 - Lint
chore($iframe.xss.response): #890 - Lint
chore($jquery-dnd): #890 - Lint
chore($jquery-plugin): #890 - Lint
chore($promise): #890 - Lint
chore($templating): #890 - Lint
chore($ui.handler.click.filebuttons): #890 - Lint
chore($ui.handler.click.filename): #890 - Lint