[hail] release 0.2.21 (#6971)

* [hail] release 0.2.21

* address comments

* add one more noteg

* bump

* address comments

hail/Makefile

@@ -11,7 +11,7 @@ BRANCH := $(shell git rev-parse --abbrev-ref HEAD)
 URL := $(shell git config --get remote.origin.url)
 SPARK_VERSION := 2.4.0
 HAIL_MAJOR_MINOR_VERSION := 0.2
-HAIL_PIP_VERSION := $(HAIL_MAJOR_MINOR_VERSION).20
+HAIL_PIP_VERSION := $(HAIL_MAJOR_MINOR_VERSION).21
 
 $(eval $(call ENV_VAR,REVISION))
 $(eval $(call ENV_VAR,SHORT_REVISION))

hail/python/hail/docs/change_log.md

@@ -1,5 +1,32 @@
 # Change Log
 
+## 0.2.21
+
+Released 2019-09-03
+
+### Bug fixes
+- (hail#6945) Fix `expand_types` to preserve ordering by key, also affects
+    `to_pandas` and `to_spark`.
+- (hail#6958) Fix stack overflow errors when counting the result of a `Table.union`.
+
+### New features
+- (hail#6856) Teach `hl.agg.counter` to weigh each value differently.
+- (hail#6903) Teach `hl.range` to treat a single argument as `0..N`.
+- (hail#6903) Teach `BlockMatrix` how to `checkpoint`.
+
+### Performance
+- (hail#6895) Improve performance of `hl.import_bgen(...).count()`.
+- (hail#6948) Fix performance bug in `BlockMatrix` filtering functions.
+- (hail#6943) Improve scaling of `Table.union`.
+- (hail#6980) Reduce compute time for `split_multi_hts` by as much as 40%.
+
+### `hailctl dataproc`
+- (hail#6904) Add `--dry-run` option to `submit`.
+- (hail#6951) Fix `--max-idle` and `--max-age` arguments to `start`.
+- (hail#6919) Add `--update-hail-version` to `modify`.
+
+---
+
 ## 0.2.20
 
 Released 2019-08-19