Fix for rich comparison and add test for vec3 file

As __cmp__ no longer in Python 3 need to use functools.total_ordering which is in 2.7 and 3.*
  https://docs.python.org/2/library/functools.html#functools.total_ordering
  https://docs.python.org/3/library/functools.html#functools.total_ordering
  Define __eq__ and __lt__ and others are created automatically

Add unittest style for file vec3.py
Fix for repr and add unit test for event

Face of cube is always an integer and entityId should always be discrete integer
So use :d instead of :2f

Add unit test of event.py
Add unittest as separate file
Revert to original verison of test file
Remove ordering and property dceorators

Use just __eq__ and __ne__ fro comparison
Remove property decorator
Add missing function brackets in length function
Update test in response
Remove runner code
Rename to indicate unittest form
Remove runner code
Change evnt to event and remove setUp/teardown
Revert event repr to previous and test

revert to previous style of repr
Add test for original event
Don't need to cov in an arm ARCH
Only try to build chroot etc. when ARCH=arm, else run tests normally
Move to PEP8 naming

Change variables and functions to lower_case
Only need to run envvars.sh when inside chroot
Install needed Python packages when outside chroot
Because Ubuntu isn't Debian

GUEST_DEPENDENCIES is for a Wheezy arm instance; without that we're on
Precise, so no python3-pip for example
Run coveralls under Python 2.7 for convenience

Ubuntu Precise, the current Travis version, doesn't provide
`python3-pip`. As an experiment, and since this is "only" test coverage,
this drops coverage run to ("native") 2.7 rather than faff with getting
a Python 3 pip as "pip" or doing some sort of conditional hackery on the
"pip install" to use "pip-3.2" in some cases.
Source envvars.sh inside run_tests if it exists

Slightly clutching at straws here but it seems like
e9f5ce62431757bd0a98fae39913e3138c2acb5b broke the tox filter; I believe
that's because of environment variables / lack of export / subshell
mechanics that this _should_ fix...
Don't allow failures of cov, since it now passes
File convention was spaces, not tabs, sorry!