"HopLite" version of SRI Testing

• Pruning the release 2# down to size as the SRI Testing 'light' version, branch code-named 'Hoplite' (an ancient Greek civilian soldier). 'Hoplite' is essentially lacking the TRAPI schema and Biolink Model validation of TRAPI Responses and simply verifies that test input edges are recovered in the TRAPI Response results. Setting the environment variable 'FULL_VALIDATION' to any non-empty value (default: None) triggers the original 'full' validation. The Test Run Summary JSON report has a 'mode' tag set accordingly either to value "FullComplianceValidation" or "HopLite".