Move user defined settings to settins.py

* Move all user defined settings in settins.py in the top level
  project directory.
* Keep all application constants in src/mist/io/config.py
* Expose all settings from settings.py in config.py
update hpcloud branch
fix openstack ssh deploy
increase max_times for deploy of a server
add alternate usernames for hp cloud deployments
fix indentation
fix enable monitoring for OpenStack
refactor add_backend
fix typo in add backend
SSH key disassociation fix
Fix ability to delete key association with old backend.

Don't check if backend_id in user.backends when disassociating keys,
so that old associatiations with machines in removed backends can
be deleted.
Fix stupid logic error that caused redundant ssh connections.
Fix issue with last key not disassociating properly in some cases
Fix issue with bash script that removes keys from authorized_keys

The command sent over ssh when associating keys looked like:
grep -v "$pub_key" ~/.ssh/authorized_keys > ~/.ssh/authorized_keys.tmp &&
mv ~/.ssh/authorized_keys.tmp ~/.ssh/authorized_keys

However, when dissasociating the last key, grep -v returns empty string.
That is seen as an error status so '&& mv' never gets executed.

That means we were never actually able to disassosiacate the last
remaining SSH key from authorized keys.

Changed '&&' to ';' so that mv is always executed.
Merge pull request #37 from mistio/shell_fix

Shell hot fix
Fix issue with missing new line in end of authorized_keys

Change key deployment bash script to gracefully handle the
case where there is no new line in the end of authorized_keys.
Merge pull request #38 from mistio/disassoc_key_fix

Disassoc key fix
Merge branch 'master' into conf
Pep8 fixes in config.py
Merge pull request #39 from mistio/conf

Conf