Badge and card holder - no support

this is clearly inspired to some badgeholder you may find on thingiverse, with 2 major modification.
1) the height of the groove can accomodate 2 badges (we use it for the badge and the coffe card), which is so useful.
2) I added a thin wall with holes to allow for the printing without support of the upper edge
in the 2019 version this thin wall has been now modified with a bigger base to prevent adhesion issues and make it easy to remove. see purple part in the picture
3) the base of the ba