Remove need for unnecessary boto.ec2 import
Remove need for unnecessary boto.ec2 import

Modules shouldn't need to import boto.ec2.
The check was to test if profile_name was supported by boto.
Two years after the introduction of the support, we will now
assume that if people are passing `profile`, they are using
a version of boto that supports it (this requirement is
already documented in the aws documentation fragment)

Also remove even older version check for `validate_certs`

Fixes #1901

thaim/ansible,thaim/ansible