AWS_KEYNAME - documentation change in create_director_image.sh file

[sbolneni]

Modify the comments for the below:

AWS_KEYNAME - absolute path to the AWS name of the key

AWS_KEYNAME=toby-aws

Change the comment to - AWS_KEYNAME - File name of the key.

If the pem file name is sbolneni-nvirgina.pem then the parameter should be...
AWS_KEYNAME=sbolneni-nvirgina