Update README.md and rename dev.sh bash script

Author: RadoBuransky

plugin/README.md

@@ -1,11 +1,4 @@
 # Sonar Scoverage Plugin source code #
 
 Useful bash script for plugin development to stop Sonar server, build plugin, copy it to Sonar plugin
-directory and start Sonar server again:
-
-    <SONAR_INSTALL_DIR>/bin/linux-x86-64/sonar.sh stop
-
-    mvn install
-    cp ./target/sonar-scoverage-plugin-1.0-SNAPSHOT.jar <SONAR_INSTALL_DIR>/extensions/plugins/
-
-    <SONAR_INSTALL_DIR>/bin/linux-x86-64/sonar.sh start
+directory and start Sonar server again is in the `dev.sh` file.

plugin/dev.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+SONAR_HOME=~/bin/sonarqube-4.2
+PLUGIN_VERSION=4.2.0
+
+mvn install
+
+PLUGIN_FILE="./target/sonar-scoverage-plugin-$PLUGIN_VERSION.jar"
+if [ ! -f $PLUGIN_FILE ]; then
+    echo "Plugin jar not found! [$PLUGIN_FILE]"
+    exit 1
+fi
+
+$SONAR_HOME/bin/linux-x86-64/sonar.sh stop
+
+rm $SONAR_HOME/extensions/plugins/sonar-scoverage-plugin-*
+cp $PLUGIN_FILE $SONAR_HOME/extensions/plugins/sonar-scoverage-plugin-$PLUGIN_VERSION.jar
+
+$SONAR_HOME/bin/linux-x86-64/sonar.sh start