### Added
- Add function to correctly extract trace id in all contexts #1125
### Fixed
- Attach fatal errors to userland root span on PHP 5.6 + PHP 5.5 #1109
- Rebuild CentOS 6 containers #1116
- NullLogger is essential, not optional #1113
- Make Uri to resource name normalization case insensitive #1120
- Avoid empty resource names in Yii in case of root `/` paths #1122
- Fix multiple deferred integration loading on PHP from 7.0 to 7.2 #1121
- Fix error in case of x-datadog-origin header in distributed tracing on PHP 7.0-7.2 #1124