[CALCITE-7037] Release Calcite 1.40.0

    1. Add and curate release notes for 1.40.0
    2. Update README and howto to refer to 1.40.0
    3. Update .mailmap with coordinates of new contributors

Author: asolimando

.mailmap

@@ -37,6 +37,7 @@ Chunhui Shi <[email protected]>
 Chunwei Lei <[email protected]>
 Chunwei Lei <[email protected]>
 Chunwei Lei <[email protected]>
+Chuxin Chen <[email protected]>
 Daniel Henneberger <[email protected]>
 Daniel Henneberger <[email protected]>
 Danny Chan <[email protected]>
@@ -157,6 +158,8 @@ Vova Vysotskyi <[email protected]>
 Wang Yanlin <[email protected]>
 Wang Yanlin <[email protected]>
 Wang Zhao <[email protected]>
+wangdiao <[email protected]>
+Wei Zhou <[email protected]>
 Weijie Wu <[email protected]>
 Wenhui Tang <[email protected]>
 Wenrui Meng <[email protected]>
@@ -184,5 +187,6 @@ Zhengqiang Duan <[email protected]>
 Zhiqiang He <[email protected]>
 Zhiqiang He <[email protected]>
 Zhong Yu <[email protected]>
+zhuyufeng <[email protected]>
 Zou Dan <[email protected]>
 Zuozhi Wang <[email protected]>

README

@@ -1,4 +1,4 @@
-Apache Calcite release 1.39.0
+Apache Calcite release 1.40.0
 
 This is a source distribution of Apache Calcite.