Duplicate/missing import

Fixes #2026 and #2027.

Able to use "environment: " on any task to pass proxy details and other useful settings.  Can be a variable
or a dictionary.

Correct -u description in ansible man page

make things like $FILE(/etc/path/foo.conf) and $ENV(HOME) work without having to use brackets to index them

Change the 0.X part to not imply something new was added in 0.X something if a user forgets to put in a specific version in the module docs.

Had to remove the instance_tags example because our doc generator was choking on it, feel free to add it back if you can get it to be valid
YAML again :)

Add rabbitmq_vhost module.

Add more error handling to the ec2 module, remove Python 2.6ism

Simply ensures existence or non-existence of a vhost.

Adding rabbitmq modules

    Changed ami_tags to instance_tags to better follow naming convention
    Add support for creating tags on the new instances

Slightly friendlier error on missing hosts file, slightly friendlier error on inventory script returning invalid syntax
(or if inventory is non-script and accidentally executable).

Signed-off-by: Brian Coca <briancoca+dev@gmail.com>