v0.4.0 support NoCtx for convenience functions

• convenience functions now support passing nil for ctx (understood as NoCtx() logging)
• documentation updates

v0.3.0 support log event callback

add support for log event callback

v0.2.0

support default value for request id

v0.1.2

update documentation

add tracing support

v0.1.1

add request id retriever callback

initial beta release

v0.1.0

add convenience functions and complete test coverage