Remove support for old Swift memcache interface.

Since this has  been removed since a year, it's time to clean this up.

Change-Id: I6681a31f675f2178285dadea876af1fdb7a8a4c3
Python 3: call functions from memcache_crypt.py with bytes as input

These functions expect bytes as input, but in Python 3 they were given text
strings.

Change-Id: I39fa15b8d5d56dc536e0bd71a50cf27da3d03046
Python3: use six.moves.urllib.parse.quote instead of urllib.quote

This makes the code compatible with both python 2 and 3.

Change-Id: Ic1c5c8d4a85db138a8402ea4b3208828fc118a40
Make sure to unset all variable starting with OS_

Some OS_ variables are conflicting with the tests, make sure to unset
them before starting the CLI tests.

Change-Id: Ie4ef467571137a685976d36026866889f7a2a1a8
Closes-Bug: 1278144
Merge "Remove support for old Swift memcache interface."
Merge "Make sure to unset all variable starting with OS_"
Merge "Python3: use six.moves.urllib.parse.quote instead of urllib.quote"
Merge "Python 3: call functions from memcache_crypt.py with bytes as input"