update es to 5.4.2

Author: medcl

README.md

@@ -11,8 +11,8 @@ Versions
 IK version | ES version
 -----------|-----------
 master | 5.x -> master
-5.4.1| 5.4.1
-5.3.2| 5.3.2
+5.4.2| 5.4.2
+5.3.3| 5.3.3
 5.2.2| 5.2.2
 5.1.2| 5.1.2
 1.10.1 | 2.4.1

pom.xml

@@ -12,7 +12,7 @@
     <inceptionYear>2011</inceptionYear>
 
     <properties>
-        <elasticsearch.version>5.4.1</elasticsearch.version>
+        <elasticsearch.version>5.4.2</elasticsearch.version>
         <maven.compiler.target>1.8</maven.compiler.target>
         <elasticsearch.assembly.descriptor>${project.basedir}/src/main/assemblies/plugin.xml</elasticsearch.assembly.descriptor>
         <elasticsearch.plugin.name>analysis-ik</elasticsearch.plugin.name>