Having the scripts in the same directory with library code means that
it'll be installed unconditionally regardless of version check in
setup.py which makes it impossible to write separate tests for python 2
and 3. Fix this by moving the scripts into separate directory and
adjusting init and setup files accordingly.
This is necessary for implementing proper CI tests in follow-up patches.
Change-Id: I30cdf0f85b2a60a235960911c9827f4129da40db