Start separating Makefiles for Linux and MacOS.
Add "clean" target.
GCC (at least on Linux) requires "gnu99" instead of "c99".
Compiling fails with "-liconv" on Linux.
Math functions (sin, cos, sqrt) require "-lm" on Linux GCC.
Add .gitignore
Whitespace only (newline at EOF).
Add "getworld" that is using the online Overpass variant.
Ignore OSM files.