DO-90/fixed_ssh_connect (#6)

*Update git class
* Add jenkins class

src/tech/avroid/jenkins/Jenkins.groovy

@@ -0,0 +1,34 @@
+package com.ncloudtech.jenkins
+
+import hudson.model.Result
+import jenkins.model.CauseOfInterruption
+import jenkins.model.Jenkins
+
+/**
+ * Class is for working with Jenkins
+ */
+class Jenkins implements Serializable {
+
+    // See https://www.baeldung.com/java-serial-version-uid
+    private static final long serialVersionUID = 1L
+
+    /**
+     * Method cancel previous builds
+     * @param jobName       String - name of currentJob
+     * @param buildNumber   int - build number of current job
+     * @param currentBuild  current build information
+     */
+    static void cancelPreviousBuilds(String jobName, int buildNumber, def currentBuild) {
+        def currentJob = jenkins.model.Jenkins.instance.getItemByFullName(jobName)
+
+		for (def build : currentJob.builds) {
+			def exec = build.getExecutor()
+			if (build.isBuilding() && build.number.toInteger() < buildNumber && exec != null) {
+				exec.interrupt(
+					Result.ABORTED,
+					new CauseOfInterruption.UserInterruption("Job aborted by #${currentBuild.number}")
+				)
+			}
+		}
+    }
+}