Merge remote-tracking branch 'upstream/master' into release_v4.7.4

# Conflicts:
#	framework/src/main/java/org/tron/program/Version.java
#	framework/src/test/java/org/tron/core/db/ManagerTest.java

Author: halibobo1205

framework/src/main/java/org/tron/common/cache/CacheManagerTest.java

@@ -0,0 +1,14 @@
+package org.tron.common.cache;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class CacheManagerTest {
+
+  @Test
+  public void allocate() {
+    String strategy = String.format(CacheStrategies.PATTERNS, 1, 1, "30s", 1);
+    TronCache<String, String> cache = CacheManager.allocate(CacheType.witnessStandby, strategy);
+    Assert.assertNull(cache.getIfPresent("test"));
+  }
+}