* add hashfunc field to EntryFormatter struct and adjust NewEntryFormatter function and tests
* add HeaderAdjuster interface and require it in EntryFormatter
* adjust all references to NewEntryFormatter to include a HeaderAdjuster parameter
* replace use of hash function in AuditedHeadersConfig's ApplyConfig method with Salter interface instance
* export audit.NewEvent function and adjust function signature
* add eventlogger based handling in LogRequest
* adjust eventlogger.Broker according to number of backends
* record auditing metrics
* only send events if a pipeline is registered
* remove TODO comments
* remove unused struct and method
* move setup of audited headers earlier into Core's initialization
* adjust entry_formatter to properly handle request headers
* protect against potential segmentation fault
* moved common code out of both switch cases
* protect against case where a.Data.Request or a.Data.Request.Headers is nil
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Co-authored-by: Peter Wilson <peter.wilson@hashicorp.com>
* add hashfunc field to EntryFormatter struct and adjust NewEntryFormatter function and tests
* add HeaderAdjuster interface and require it in EntryFormatter
dquote> adjust all references to NewEntryFormatter to include a HeaderAdjuster parameter
* replace use of hash function in AuditedHeadersConfig's ApplyConfig method with Salter interface instance
* fixup! replace use of hash function in AuditedHeadersConfig's ApplyConfig method with Salter interface instance
* review feedback
* Go doc typo
* add another test function
---------
Co-authored-by: Peter Wilson <peter.wilson@hashicorp.com>
