Documentation of API host

Add in the documentation something to explain this:

to install openserverless you need admin access to a kubernetes cluster
with an ingress and point an entire domain to the ip of the ingress,
if you want also ssl you need to add also the cert-manager

before installing you need to correctly set the apihost with
`ops config apihost [--tls=|--protocol=(https|https)]`
enable the services you want
`ops config enable --all`
and then install with
`ops setup kubernetes create`

in the more general case you (https with public ip and ssl) once you created the the domanin (* and @ records pointing to the ingress ip) you do

ops config apihost sciabarra.net --tls=
ops config enable --all
ops setup kubernetes create

if you want to do a local install we have a special domain, miniops.me with *.miniops.me and miniops.me points to 127.0.0.1, this is for private installation, localhost only.

In this case you do:

ops config apihost miniops.me
ops config enable --all
ops setup kubernetes

note that in this case you are going to use http:

you may also have an https load balancer in front of the server

in this case you do

ops config apihost external-domain --protocol=https
ops config enable --all
ops setup kubernetes

in this case the service is internally http but externally is served as https so you do not need a cert-manager but provision an external load balancer

# miniops

doing `ops setup mini` enable all the services set the apihost to miniops and installs a devcluster (a kind cluster)

まず、インストールのドキュメントと `ops` コマンドのリファレンスを見つけます。Kubernetes、TLS、local miniops、external-load-balancer、`ops setup mini` のワークフローを、issue 内のコマンドと照合して検証します。各セットアップパス、前提条件、プロトコル、例が正確にドキュメント化されていれば完了です。

索引モデルが issue の本文から書いたものです。