Merge branch 'master' of https://github.com/furrtek/portapack-havoc

sdcard/README.md

 # How to generate world_map.bin
 
-World_map.bin is a huge (~450MB) raw image file in a format that can be easily rendered by the PortaPack.
+World_map.bin is required if you want to use the world map view in some apps. It's a huge (~450MB) raw image file in a format that can be easily rendered by the PortaPack.
+
 Since Github doesn't allow uploading such large files, you must generate it yourself from the provided jpg file.
 
 1. Make sur that `world_map.jpg` is in `/sdcard/ADSB`.
 1. Go in `/firmware/tools`.
 1. Run 'python adsb_map.py'. Give it some time.
-1. `world_map.bin` should appear !
+1. `world_map.bin` should appear ! Leave it in the ADSB directory.