New features and bug fixes:

• XGBoost classification & regression models - EXPERIMENTAL #44
• Add default param grid for xgboost #175
• Fix ModelInsights for xgboost #170
• Added Parquet reader #169
• Added aggregate & conditional readers for Parquet #172
• Evaluators check for empty data #178
• Refactored splitter tests #176
• Return scoring feature distributions from RawFeatureFilter #171
• Using MapReduce Api for Avro Read Write #150
• Improve test coverage for VectorsCombiner and make vector aggregator efficient #168
• Time based aggregators #167
• Ignore null values in meta + support floats #166
• CLI command name fix + bump shadow plugin version + cleanup #164
• Fix build.sbt example in readme #165
• Removed an old test I added to check if Spark ran out of memory when calculating a correlation matrix (this is unnecessary and unhelpful) #160
• Replace assert with require #159
• Streaming histogram implementation #152
• Added test and removed dead code for Sanity Checker dealing with map with same key #153
• Fixed model insights exception when features are excluded from sanity checker correlation calculations #147
• Added logging of response distribution to RFF #146
• Use proper test ranges in feature converter test #143
• Added support for DateType and TimestampType primitive spark types #135
• Standardizing timezone to UTC #138

Dependency upgrades & misc:

• XGBoost 0.81 #180
• Spark 2.3.2 #44
• Gradle 4.10.2 #142
• Use OpenJDK8 for CircleCI builds + refactor build config #140