0.8.0 / 2016-08-17

• [CHANGE] Registry is doing more consistency checks. This might break
  existing setups that used to export inconsistent metrics.
• [CHANGE] Pushing to Pushgateway moved to package push and changed to allow
  arbitrary grouping.
• [CHANGE] Removed SelfCollector.
• [CHANGE] Removed PanicOnCollectError and EnableCollectChecks methods.
• [CHANGE] Moved packages to the prometheus/common repo: text, model,
  extraction.
• [CHANGE] Deprecated a number of functions.
• [FEATURE] Allow custom registries. Added Registerer and Gatherer
  interfaces.
• [FEATURE] Separated HTTP exposition, allowing custom HTTP handlers (package
  promhttp) and enabling the creation of other exposition mechanisms.
• [FEATURE] MustRegister is variadic now, allowing registration of many
  collectors in one call.
• [FEATURE] Added HTTP API v1 package.
• [ENHANCEMENT] Numerous documentation improvements.
• [ENHANCEMENT] Improved metric sorting.
• [ENHANCEMENT] Inlined fnv64a hashing for improved performance.
• [ENHANCEMENT] Several test improvements.
• [BUGFIX] Handle collisions in MetricVec.