In `psrand.h` it attempts to undefine RAND_MAX and then redefine it.
This may work on some compilers but G++/Clang. To resolve this error
RAND_MAX was renamed to D3_RAND_MAX but **only** in files that
included `psrand.h`. The code behavior should restored to that of the
official release.
Join the license header with historical comments using a separator so IDEs can correctly parse the initial header.
Also use .gitattributes to ensure all files are LF.
The MACINTOSH define refers to MacOS Classic (not OS X) which we do not
plan to support. Rather than carry the cruft forever, let's delete it.
NOTE: legacy/ is unused but we're keeping it around, so MACINTOSH uses
there are left alone.
Process used for this commit:
```
git rm -r mac
find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" \) \
-exec unifdef -UMACINTOSH -o {} {} \;
git restore legacy
git add .
```
Test Plan:
On Mac, build both Debug and Release
```
cmake --build --preset mac --config Debug
cmake --build --preset mac --config Release
```
