Committing first example file.

X-Signed-Off-By: Matt Nunes
Committing the second example file.

X-Signed-Off-By: Matt Nunes
Committing the third exercise file.

X-Signed-Off-By: Matt Nunes
Committing the fourth exercise file.

X-Signed-Off-By: Matt Nunes
Adding to the README; committing a Makefile.