Can't login to update key or curl submit

keybase-user: robbat2
log-id: 29b76c3b9bb947b1ed62671c

```
$ keybase login robbat2
▶ ERROR during GPG provisioning.
We were able to generate a PGP signature with gpg client, but it was rejected by the server. This often means that this PGP key is expired or unusable. You can update your key on https://keybase.io
▶ ERROR Key corrupted: Could not open key: no valid primary key self-signature or key(s) have expired
```

And using the gpg+curl method to sign the update, I get:
```
Error in your post
-------------------

Code: 915
Name: KEY_BAD_UIDS
Description: You can't delete your keybase.io username
* Connection #0 to host keybase.io left intact
```

w/ `curl -v`:
```
* Trying 52.6.136.121...
* TCP_NODELAY set
* Connected to keybase.io (52.6.136.121) port 443 (#0)
* Initializing NSS with certpath: none
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: none
* ALPN, server accepted to use http/1.1
* SSL connection using TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
* Server certificate:
* subject: CN=keybase.io,OU=PositiveSSL,OU=Domain Control Validated
* start date: May 18 00:00:00 2018 GMT
* expire date: Jun 17 23:59:59 2019 GMT
* common name: keybase.io
* issuer: CN=COMODO RSA Domain Validation Secure Server CA,O=COMODO CA Limited,L=Salford,ST=Greater Manchester,C=GB
> POST /_/api/1.0/key/add.json HTTP/1.1
> Host: keybase.io
> User-Agent: curl/7.55.0
> Accept: */*
> Content-Length: 32271
> Content-Type: application/x-www-form-urlencoded
> Expect: 100-continue
>
< HTTP/1.1 100 Continue
* We are completely uploaded and fine
< HTTP/1.1 200 OK
< Date: Wed, 14 Nov 2018 23:45:38 GMT
< Content-Type: text/html; charset=utf-8
< Content-Length: 124
< Connection: keep-alive
< Vary: X-HTTP-Method-Override
< X-Frame-Options: SAMEORIGIN
< X-XSS-Protection: 1; mode=block
< X-Content-Type-Options: nosniff
< ETag: W/"7c-u/3tVHjxbrkDn/M1Q9l6mH44TX8"
< Strict-Transport-Security: max-age=31536000; includeSubdomains; preload
<
Error in your post
-------------------

Code: 915
Name: KEY_BAD_UIDS
Description: You can't delete your keybase.io username
* Connection #0 to host keybase.io left intact
```

Start with the `keybase login robbat2` GPG provisioning flow and the `/_/api/1.0/key/add.json` endpoint shown in the report. Reproduce the expired-key and `KEY_BAD_UIDS` cases, then trace how the client submits the key update; done means the user can update the key and log in without either error.

Written by the indexing model from the issue text.