perl 5.003_01: mg.c

perl 5.003_01: mg.c

Use safefree() instead of Safefree to free memory allocated by safemalloc()
Add support for shared hash keys
Add $^E support for OS/2
Add support for 64-bit time values
Add cast for new GV type
Don't allow errors in setting string $! to change $!
Restart system calls on all signals where possible
Add support for imporved %SIG management
Don't reset global $. unless we're reading a file