OPENDAP/bes: Version 3.20.6 for Hyrax 1.16.1

Performance Improvements No DAS construction for data response. Bugs Fixed Memory leak fixed and unneeded copy removed in awsv4 code CovJson patch. ncml_handler: When an NCML aggregation named a dataset that the server could not read... crsh. Fixed.. Server cache stabliszation Added (alpha) support support for server authentication credentials: Environment injection support for besstandalone and besd A credentials configuration file for multiple sets, in which credentials are asscoaied with URL prefixs and multiple creds can be defined in a bes.conf environment. Combined Logs: The server can now be configured to add the OLFS request log content to the BES log. hdf4_handler: Fixed memory leaks hdf5_handler: Fixed memory leak