add content-length to HEAD responses. fixes: #116
key.size now reflects the same behavior as boto, added unit test

Conflicts:
	moto/s3/responses.py
respect port in mockaws urls
add url with port for mock aws s3

Conflicts:
	moto/s3/urls.py
add mock host for STS
Fixed s3 key size test for different boot versions. requires_boto_get decorator no longer skips all tests in module. Added unittest2 to requirements.txt. Added requires_boto_get decorator to tests that now need it.
don't let flask automatically set the content length
Merge branch 'contentlen' into longaccess
adding - get all certificates, get certificate, and upload certificates endpoints
Add @matafc to authors.
Attribute instance-id added to filter dict
add test for instance filtering by instance-id
Merge pull request #136 from wittwerch/master

Allow instance filtering by instance-id
Implement internet gateway mocking
switch to using boto's SpotInstanceRequest in backend
Merge pull request #138 from IlyaSukhanov/master

Implement internet gateway mocking
add Model metaclass to collect model accessor methods from backend classes
provide SpotRequestBackend with model accessor
Enhanced SQS support

- Support for delaying messages
- Support for visibility timeouts
- Support for actually deleting messages
- Support for message bodies longer than 27 characters
- Support for message attributes
- Support for accurate queue attributes

Caveats:

- All message attributes are returned regardless of whether or not
attributes were requested when reading messages
- I’m not sure why messages longer than 27 characters were breaking in
my tests. Boto seems to expect the body to be base64 encoded and bodies
less than 27 characters would be fine, but if I attempted to use a
larger body it would mangle the content. I now base64 encode the body
if the raw string is longer than 27 characters and all is fine.
get total seconds that works in >2.3