Removing zone choices that overly-limit available zones for gce

Fixes #7270
Fixing two bugs in the ec2_elb_lb module

* the current state of the ELB was not reflected properly when checking
  the status after a change was made.
* invalid zones caused a traceback when enabling/disabling zones
ignore remnants from doing a setup.py install
Merge pull request #7282 from ephur/gitignore_egginfo

ignore remnants from doing a setup.py install
Make sure amazon test doesn't check host keys
Update packaging dates for the 1.6.0 release
Version bump for 1.7
Update RELEASES.txt
Update CHANGELOG.md
django_manage: added generatemedia to the command options