Added release script

Author: MatthiasValvekens

pom.xml

@@ -6,9 +6,10 @@
 
     <groupId>com.itextpdf.research</groupId>
     <artifactId>xfdf-merge</artifactId>
-    <version>1.0-SNAPSHOT</version>
+    <version>${revision}</version>
 
     <properties>
+        <revision>1.0-SNAPSHOT</revision> <!-- "revision" is special, anything else triggers a warning -->
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.source>11</maven.compiler.source>
         <maven.compiler.target>11</maven.compiler.target>

release.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+
+# Script to generate jars with the current date in them
+
+generate_version() {
+xmllint --shell pom.xml <<EOF | grep -E -v '^/|^ ' | sed "s/SNAPSHOT/$(date --utc +%Y%m%d)/"
+setns ns=http://maven.apache.org/POM/4.0.0
+cat /ns:project/ns:properties/ns:revision/text()
+EOF
+}
+
+VERSION_STR=$(generate_version)
+
+echo "Building version $VERSION_STR..."
+mvn package "-Drevision=$VERSION_STR"