`Writer' protocol change.

[tonystone]

• Added LogEntry tuple type to Writer defining the formal types that a Writer writes.
• Changed Writer protocol log(timestamp:level:tag:message:runtimeContext:staticContext:) method to write(_ entry: Writer.LogEntry) to make it easier to process messages by writers and formatters.

[codecov[bot]]

Codecov Report

Merging #74 into release-5.0 will increase coverage by <.01%. The diff coverage is 100%.

@@               Coverage Diff               @@
##           release-5.0      #74      +/-   ##
===============================================
+ Coverage        99.13%   99.13%   +<.01%     
===============================================
  Files               22       22              
  Lines              576      578       +2     
===============================================
+ Hits               571      573       +2     
  Misses               5        5

Impacted Files	Coverage Δ
Sources/TraceLog/Logger.swift	87.09% <ø> (ø)	:arrow_up:
Sources/TraceLog/Formatters/JSONFormat.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLogTestHarness/BufferReader.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLogTestHarness/BufferWriter.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLog/Writers/FileWriter.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLog/Proxies/AsyncWriterProxy.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLog/Formatters/TextFormat.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLog/Proxies/SyncWriterProxy.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLogTestHarness/TestHarness.swift	100% <100%> (ø)	:arrow_up:
Sources/TraceLog/Writers/ConsoleWriter.swift	100% <100%> (ø)	:arrow_up:
... and 1 more