added base flag to one suppression entry
added base attribute to suppression rules
added the base=true flag to all base suppressions
corrected the removal of an identifier so that iterator.remove was correctly used
added parsing of the base flag
added the base property and skipped adding the vulnerability or identifier to the suppressed collection if this is a base suppression rule
added assertion to validate that the base flag is being processed
added test cases to ensure setting the base flag will prevent the identifier from being added to the suppressedIdentifiers collection