Update erlcloud_ec2.erl

Support multiple security groups when no network specs defined.
Merge pull request #114 from jvanvleet/master

Support multiple security groups when no network specs defined.
Minor fixes
Updated GSI KeySchema to support both hash key and hash-and-range key
Merge pull request #115 from smilerlee/master

Updated GSI KeySchema
Add https procol support for sns
Remove unnecessary catch()
Change sns_protocol config field to sns_scheme
Add test for case-insensitivity
Mock request at the erlcloud_httpc level
Test for HTTPS uppercase conversion
Cleanup commented debris
Merge pull request #117 from esl/sns-https-support

HTTPS support for erlcloud_sns
fix signature calculation on empty params

when generating a http query string on params with empty lists (ie. queue name prefix on list_queues) the equal sign was not being added next to the key name leaving the empty value (ie. QueueNamePrefix = ). This leads to a signature calculation mismatch since amazon performs the calculation of their side using the equal sign.
fix sqs get queue attributes method

was missing xml attributes: ApproximateNumberOfMessagesDelayed, DelaySeconds, ReceiveMessageWaitTimeSeconds
Merge pull request #120 from lrascao/fix_sqs_list_queues

fix signature calculation on empty params
Merge pull request #121 from lrascao/fix_sqs_get_queue_attributes

fix sqs get queue attributes method
Remove .orig file
vsn 0.9.1
Fix various warnings

- Fix imports that are not used
- Fix exported variables from case or if statements
- The problems are important when warnings_as_errors is turned on