Unit Tests: one more CentOS compatability fix

Apparently C has macros for 64bit printf formats across different system
architectures.

See this SO answer: http://stackoverflow.com/a/9225648/13216
Merge unit-tests-centos-5-compatability (#5) into ifixit-production

Unit Tests: one more CentOS compatability fix

Apparently C has macros for 64bit printf formats across different system
architectures.

See this SO answer: http://stackoverflow.com/a/9225648/13216