Caches iButton values
Changed FIFO management to try to remove on exit
Made math work properly in python 2 and 3

Old code was doing an integer division, essentially useless
Merge pull request #11 from msoucy/fifo

Changed FIFO management to try to remove on exit
Merge pull request #10 from msoucy/cache

Caches iButton values
Merge pull request #12 from msoucy/math

Made math work properly in python 2 and 3