MIME types doesn't support underscore symbol

[IvanGoncharov]

According to IANA, underscores are supported. For example: "audio/ip-mr_v2.5" or "vnd.ntt-local.sip-ta_remote"

[webron]

You mean it's not supported by the json schema?

[IvanGoncharov]

Yes. Right now, mimeType validated against "^[\sa-z0-9-+;.=/]+$" which is missing underscore.
I create pull request #269

[webron]

Thanks, but we're actually going to make it much more permissive soon, see #128. Please subscribe to that issue to get updates.

[IvanGoncharov]

Thank you.

[webron]

Thank you for taking the time to report it and create a PR though. I really appreciate it. If you have any input with regards to the info at #128, please feel free to add it there.