ioshield for the asrockrack b450d4u-v1lq5 supermicro CSE-512 1u

The asrockrack board b450d4u-v1lq5 is beig sold at a very good price some cases were needed. had some supermicro CSE512 left over, combine them, started from the very identical board x470d4u (that has more connectors). 

todo's:

• no holes yet for screws. : fixed in v1.5
• the connectors at the bottom need to be slimmer,  fixed in v1.5
• the margin around the vga connector needs to be increased fixed in v1.5
• add opening for the top case cover clip : fixed in v1.5

the thickness of the shield is ok.

similar Asrockrack board but different connectors