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Filenames may be dropped when collated (Browserify, Polymer, X-Tag) or relayed via CDN.  So I added the filename & copyright info into `Gruntfile.coffee`.  `!` & `@licence` are flags to help minifiers prevent remvoal.
Test worked locally: `/*! mailcheck v1.0.4 (c)2012 Received Inc, @licence MIT */`
Merge pull request #82 from tomByrer/patch-1

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