SVGs wrongly classified as `image/svg`. Should be `image/svg+xml`.

[Asheboy]

The mime returned for SVGs is returned as image/svg, where as the latest libmagic returns image/svg+xml. I think it was this change in libmagic which has caused the change file/file@1a08bb5#diff-ef0f1096db6eb16f194642478eeb447c062f5dac100af139785a45bc6d1b3404.