Check for the duplicated rule when adding a new security group rule, and disable the "Add rule" button if detected.
isDuplicatedRule to hasDuplicatedRule
Added comments for the duplicated rule detection process
Added comments on the compareRules logic
Changed the error message from "Security group already exists" to "Rule already exists"
Removing unused CSS classes for the security group rule panel
Merge pull request #210 from eucalyptus/GUI-401

Check for the duplicated rule when adding a new security group rule, and...