fix folly build under python 3

fix folly build under python 3

Summary:
Make python scripts compatible woth both python 3 and python 2.
Added ignore rule for test/glog directory.

Facebook:
While verifying some issues reported on github i noticed that
folly does not build when python 3 is the default (at least on arch
linux). As it turns out it is fairly easy to make our python files
compatible with both python 2 and python 3.
I also added test/glog*/* to gitignore so that it is easier to work
on folly outside of facebook.

Test Plan:
unit tests in fb envirnoment and unit test on arch linux
(python 3.4.2, gcc 4.9.2)

Reviewed By: njormrod@fb.com

Subscribers: trunkagent, folly-diffs@

FB internal diff: D1801368

Signature: t1:1801368:1422294777:4e7b6b5634e8dccd849194e171c9a342bd1cb8b8