consistently use 'web interface' (two words)

Signed-off-by: Matthias Heiserer <m.heiserer@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

certificate-management.adoc

@@ -33,7 +33,7 @@ the cluster CA and therefore not automatically trusted by browsers and
 operating systems.
 2. use an externally provided certificate (e.g. signed by a commercial CA).
 3. use ACME (Let's Encrypt) to get a trusted certificate with automatic
-renewal, this is also integrated in the {pve} API and Webinterface.
+renewal, this is also integrated in the {pve} API and web interface.
 
 For options 2 and 3 the file `/etc/pve/local/pveproxy-ssl.pem` (and
 `/etc/pve/local/pveproxy-ssl.key`, which needs to be without password) is used.

hyper-converged-infrastructure.adoc

@@ -46,7 +46,7 @@ Hyper-Converged Infrastructure: Storage
 
 {pve} has tightly integrated support for deploying a hyper-converged storage
 infrastructure. You can, for example, deploy and manage the following two
-storage technologies by using the Webinterface only:
+storage technologies by using the web interface only:
 
 - *ceph*: a both, self-healing and self-managing shared, reliable and highly
   scalable storage system. Checkout

pve-storage-pbs.adoc

@@ -11,7 +11,7 @@ Storage pool type: `pbs`
 This backend allows direct integration of a Proxmox Backup Server into {pve}
 like any other storage.
 A Proxmox Backup storage can be added directly through the {pve} API, CLI or
-the webinterface.
+the web interface.
 
 Configuration
 ~~~~~~~~~~~~~