Description of problem:
The fc29 version of cyrus-imapd includes a reference to the jmap http module, so the service will not start.

Version-Release number of selected component (if applicable):
cyrus-imapd-3.0.8-1.fc29.x86_64

How reproducible:
Everytime

Steps to Reproduce:
1. Create f29 vagrant box, eg with Vagrantfile:
Vagrant.configure("2") do |config|
  config.vm.box = "fedora/29-cloud-base"
end
vagrant up, and vagrant ssh
2. `sudo dnf install cyrus-imapd`
3. `sudo dnf start cyrus-imapd`

Actual results:
Service fails, including this error:
```
 invalid value 'jmap' for httpmodules in line 55
```

Expected results:
cyrus-imapd.service should start

Additional info:
the rawhide version appears to have fixed this:
```
diff /etc/imapd.conf /vagrant/imapd.conf.30 
55c55
< httpmodules: caldav carddav domainkey freebusy ischedule jmap rss tzdist webdav
---
> httpmodules: caldav carddav domainkey freebusy ischedule rss tzdist webdav
```

As this is an issue with the configuration file, would it make sense to include a note in the upgrade process that `cyrus-imapd` has removed support for `jmap`, pending the protocol stabilising, as amended `/etc/imapd.conf`s would not overwrite existing ones from earlier releases?