update es to 5.1.2

Author: medcl

README.md

@@ -11,7 +11,7 @@ Versions
 IK version | ES version
 -----------|-----------
 master | 5.x -> master
-5.1.1| 5.1.1
+5.1.2| 5.1.2
 1.10.1 | 2.4.1
 1.9.5 | 2.3.5
 1.8.1 | 2.2.1

pom.xml

@@ -12,7 +12,7 @@
     <inceptionYear>2011</inceptionYear>
 
     <properties>
-        <elasticsearch.version>5.1.1</elasticsearch.version>
+        <elasticsearch.version>5.1.2</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>