Include icon files in MANIFEST.in
Update docs to refer to install_aliases() instead of install_hooks()
Update a couple of tests to use install_aliases() instead of install_hooks()
Speed up importing of past.translation (issue #117)

Also: give more descriptive error messages if top-level packages are imported
somehow on Py3.
Add a(nother) test for issue #121

Also fix up the import-order checking code in future.tests.base
Add failing tests for the cause of issue #119

It seems that sys.exit(newint) (and other longs) always returns 1!
Fix issue #119
Remove the previous workaround for sys.exit()'s wrong exit code with newint
Fix doc bug (cheat sheet: iteritems import) (issue #120)