#184 code in markdown use plantuml syntax

[kirchsth]

fixed #184, no red blocks are displayed in code samples anymore. It can be checked via kirchsth/extended

e.g.

@startuml
!include https://raw.githubusercontent.com/kirchsth/C4-PlantUML/extended/C4_Context.puml

Person(user, "User")
Person(user1, "User 1")
Person(user2, "User 2")
Person(user3, "User 3")

System(system, "System")

' normal sprites are too big 
Rel_L(user, user2, "informs", "courier", "normal sprites are too big", $sprite="person2")

' scaled sprites are ok
Rel_R(user, user3, "informs", "courier", "scaled sprites are OK", $sprite="person2,scale=0.5")

' combine sprite and scale to a new sprite
!$combinedSprite="person2,scale=0.5"
Rel_R(user, user3, "informs", "courier", "combined sprites are OK", $sprite=$combinedSprite)


' special smaller sprites can be used
sprite $triangle {
    00000000000
    00000F00000
    0000FBF0000
    0000FBF0000
    000F999F000
    000F999F000
    00F66666F00
    00F66666F00
    0F3333333F0
    0F3333333F0
    0FFFFFFFFF0
    00000000000
}
Rel_R(user1, system, "orders", "http", "small sprites, like the small triangle", $sprite="triangle")

' if sprite starts with &, sprite defines a OpenIconic, details see https://useiconic.com/open/
Rel_D(user, user1, "requests", "async message", "if sprite starts with &, it defines a OpenIconic like &envelope-closed", $sprite = "&envelope-closed")
@enduml

BR Helmut