Cut v2.19.0-rc.0 (#7341)

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>

CHANGELOG.md

@@ -1,3 +1,16 @@
+## 2.19.0-rc.0 / 2020-06-08
+
+* [FEATURE] TSDB: Memory-map full chunks of Head (in-memory) block from disk. This reduces memory footprint and makes restarts faster. #6679
+* [ENHANCEMENT] Discovery: Added discovery support for Triton global zones. #7250
+* [ENHANCEMENT] Increased alert resend delay to be more tolerant towards failures. #7228
+* [ENHANCEMENT] Remote Read: Added `prometheus_remote_storage_remote_read_queries_total` counter to count total number of remote read queries. #7328
+* [ENHANCEMEMT] Added time range parameters for label names and label values API. #7288
+* [ENHANCEMENT] TSDB: Reduced contention in isolation for high load. #7332 
+* [BUGFIX] PromQL: Eliminated collision while checking for duplicate labels. #7058 
+* [BUGFIX] React UI: Don't null out data when clicking on the current tab. #7243
+* [BUGFIX] PromQL: Correctly track number of samples for a query. #7307
+* [BUGFIX] PromQL: Return NaN when histogram buckets have 0 observations. #7318
+
 ## 2.18.1 / 2020-05-07
 
 * [BUGFIX] TSDB: Fixed snapshot API. #7217

VERSION

@@ -1 +1 @@
-2.18.1
+2.19.0-rc.0