Custom Heart Box Updated (V3)

## All-at-once Secret Heart Box (update January 2021)

### 95% based on Emmett Lalish thing 1221494 (https://www.thingiverse.com/thing:1221494)
### 5% updated by Martin Walla (https://HD-4D.de)
- update to current SCAD syntax version, i.e. no errors/warnings (as of January 2021)
- remove dependency on external write library (use text/fonts from SCAD fontlist instead)
- add finetuning for size and position of initials
- add rounded or beveled support for upper chamber roof (especially useful for hearts scaled bigger)
- few little tweaks
- updated customizer settings

#### Sorry for being quite late for Valentines Day 2021, but anyway: I hope you have fun with this derivative of Emmett Lalish's great work!