Update readme and sdk version

Author: SaharRefua-Pipl

README.md

@@ -10,7 +10,7 @@ Library Requirements
 --------------------
 
 * Google Gson, you can find it inside this project under `lib/google/` or download from [here](http://code.google.com/p/google-gson/downloads/list).
-* The library was tested on Java 8 and above.
+* The library SDK version 5.1.0 is compatible with Java 8 and above.
 
 Installation
 ------------

pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>com.pipl.api</groupId>
     <artifactId>piplapis</artifactId>
-    <version>6.0.0-SNAPSHOT</version><!-- `-SNAPSHOT` is replaced during build -->
+    <version>5.1.0-SNAPSHOT</version><!-- `-SNAPSHOT` is replaced during build -->
     <packaging>jar</packaging>
 
     <name>${project.groupId}:${project.artifactId}</name>