Cors issues on crossref if calling from browser

[mitra42]

I'm trying to move metadata pulling to the browser, and have code that works, however in the cases of publishers that doi redirects to crossref, crossref doesnt set the Cross-Origin info, so the browser complains.
I'm not sure how to fix it, really it should be for crossref to fix, but that sounds inlikely, so for now will pull metadata from server.