v0.5.0 Release

This is a first official beta release, which provides almost fully complete metrics, tracing, and context propagation functionality but makes no promises around breaking changes.

💥 Breaking Change

• #853 Rename scope to context
• #851 Rename formatter to propagator

🚀 (Enhancement)

• #828 feat: metric observer
• #858 chore: update out-of-date dependencies
• #856 fix: change loglevel for beta
• #843 export resource to exporters
• #846 SDK Resource
• #625 feat: introduce ended property on Span
• #837 Simplify SDK registration
• #818 fix: change SpanContext.traceFlags to mandatory
• #827 Add getter and setter arguments to propagation API
• #821 feat: add composite propagator
• #824 Faster trace id generation
• #708 Simplify and speed up trace context parsing
• #802 chore: adding force flush to span processors
• #816 feat: use context-based tracing
• #815 Resources API: package, semantic conventions, and test utils
• #797 Add propagation API
• #792 Add context API
• #685 feat: add express plugin #666
• #769 Separate context propagation (OTEP 66)
• #653 Prevent loading plugins for incorrect module #626
• #654 feat: warn user when a instrumented package was already required #636
• #772 chore: add typing to propagator carrier
• #735 feat: decode jaeger header
• #719 feat(plugin-http): sync. specs for statuscode
• #701 feat: add jaeger http trace format (#696)

🐛 (Bug Fix)

• #798 Respect sampled bit in probability sampler
• #743 fix: left pad jaeger trace ids
• #715 fix: unref jaeger socket to prevent process running indefinitely