BTW plantuml-office have been integrated into standard library http://plantuml.com/stdlib
Meaning you can now have:
@startuml
!include <font-awesome/common>
!include <office/Servers/database_server>
!include <office/Servers/application_server>
!include <office/Concepts/firewall_orange>
!include <office/Clouds/cloud_disaster_red>
title Office Icons Example
package "Sprites" {
OFF_DATABASE_SERVER(db,DB)
OFF_APPLICATION_SERVER(app,App-Server)
OFF_FIREWALL_ORANGE(fw,Firewall)
OFF_CLOUD_DISASTER_RED(cloud,Cloud)
db <-> app
app <--> fw
fw <.left.> cloud
}
@enduml