InvalidLocationConstraint error in AWS S3 handled.

[GEizaguirre]

Creating a bucket with the boto3 AWS S3 client may return a InvalidLocationConstraint error, if we use the default value for an AWS region ("us-east-1") in the LocationConstraint parameter. More specifically:

ClientError: An error occurred (InvalidLocationConstraint) when calling the CreateBucket operation: The specified location-constraint is not valid

This error has been previously reported:

boto/boto3#125
boto/boto3#811

I simply propose a quick fix that retries the operation without the LocationConstraint if the region is "us-east-1".

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[JosepSampe]

Great, thanks @GEizaguirre!