upload: Media ID conversion broken

[Trek Hopton]

We used to be able to convert from MAC and Pin to MID on the upload page but this no longer works.

The elements are still there but when the convert button in clicked, nothing happens.

I have found that a change was made here in PR #30 which removed the id from the MID element therefore breaking the conversion process.

I don’t know why this was done but I see no reason we don’t add it back.

[Trek Hopton]

Resolved in PR #73