add new versioning type for MTAs

src/com/sap/piper/versioning/MtaArtifactVersioning.groovy

@@ -0,0 +1,21 @@
+package com.sap.icd.jenkins.versioning
+
+class MtaArtifactVersioning extends ArtifactVersioning {
+
+    private String baseVersion
+
+    protected MtaArtifactVersioning (script, configuration) {
+        super(script, configuration)
+    }
+
+    @Override
+    def getVersion() {
+        baseVersion = script.readYaml(file: configuration.filePath).version
+        return baseVersion
+    }
+
+    @Override
+    def setVersion(version) {
+        script.sh "sed -i 's/version: ${baseVersion}/version: ${newVersion}/g' ${configuration.filePath}"
+    }
+}