Support email and url form input types

[scop]

Since home-assistant-libs/voluptuous-serialize#8, voluptuous-serialize can include format info for strings: url, email, and fqdnurl. Would be useful to support these in HA forms. I would probably have used the url one in Huawei LTE's config UI had it been possible.

This change is completely untested, I have no idea if it works, and I'm really fairly clueless wrt this stuff, but maybe it helps someone to beat it into shape unless it by some scary luck actually works as is :)

In case it doesn't, feel free to take and finalize it, I'm not sure if I have time to get to know this stuff, I rather work on something non-UI in HA.

[bramkragten]

You are aware that this won't change much? It will only show a different keyboard on some mobile devices.

[scop]

In addition to changing the keyboard on some mobile devices (which I consider valuable already), I'd assume that it also makes browsers natively validate the fields' contents. At least that's what happens with regular HTML input fields, dunno about the HA UI ones.

[bramkragten]

In addition to changing the keyboard on some mobile devices (which I consider valuable already), I'd assume that it also makes browsers natively validate the fields' contents. At least that's what happens with regular HTML input fields, dunno about the HA UI ones.

Yes it does, and that is indeed very valuable. We might need to adjust the error messages, as it only used to check it is was required -> empty.