Add skeleton
Beginning filename initialization and main loop
Add memdiff executable to .gitignore
Check for power of two using bitops

The ever insightful scanlime suggested a better way of doing this check
with only bitops and since that's a better way of doing it, that's how
it is now being done.
Same check for -b and -k

I changed the check for -b, without realizing the same check also occurs
for -k.  Both now work the same.
Check for power of two using bitops

The ever insightful scanlime suggested a better way of doing these
checks with only bitops and since that's a better way of doing it,
that's how it is now being done.
Basic outline for file operations

Locates, opens and closes the files needed for the program.  Also mmaps
the input files and uses C standard lib file I/O to stream data to the
output files.  Doesn't actually do anything with them, yet.
Declare mmap pointers as char * instead of void *

This means the compiler understands pointer arithmetic on these better
so even though I'm not thrilled about declaring pointers like this as
char *, it is the "right" thing to do here.
Add the main logic for memdiff

This takes the existing program and makes it useful for the first time.
Memdiff now actually does differencing on the snapshots and correctly
outputs what is essentially a bitmap of blocks which change or don't
change between snapshots for each segment.
README for memdiff

Written in the style of the memsnap README, memdiff is now sufficiently
advanced enough to be useful and therefore should have a README.  It is
however, still in a state where the code is immature and may not perform
as documented.