added branch protect sample

Added a sample with README for protecting branches at the organizational level

Author: Jared Murrell

hooks/jenkins/master-branch-protect/branch-protect.Jenkinsfile

@@ -0,0 +1,79 @@
+node {
+  properties([
+    [$class: 'BuildDiscarderProperty',
+      strategy: [$class: 'LogRotator',
+        artifactDaysToKeepStr: '',
+        artifactNumToKeepStr: '',
+        daysToKeepStr: '',
+        numToKeepStr: '5']
+    ],
+    pipelineTriggers([
+      [$class: 'GenericTrigger',
+        genericVariables: [
+          [expressionType: 'JSONPath', key: 'repository', value: '$.repository'],
+          [expressionType: 'JSONPath', key: 'organization', value: '$.organization'],
+          [expressionType: 'JSONPath', key: 'sender', value: '$.sender'],
+          [expressionType: 'JSONPath', key: 'ref_type', value: '$.ref_type'],
+          [expressionType: 'JSONPath', key: 'master_branch', value: '$.master_branch'],
+          [expressionType: 'JSONPath', key: 'branch_name', value: 'ref']
+        ],
+        regexpFilterText: '',
+        regexpFilterExpression: ''
+      ]
+    ])
+  ])
+  // Define the payload to send to GitHub.
+  // This is JSON
+  def githubPayload = """{
+      "required_status_checks": {
+        "strict": true,
+        "contexts": [
+          "continuous-integration/jenkins/branch"
+        ]
+      },
+      "enforce_admins": true,
+      "required_pull_request_reviews": {
+        "dismissal_restrictions": {
+          "users": [
+            "hollywood",
+            "primetheus"
+          ],
+          "teams": [
+            "test-team"
+          ]
+        },
+        "dismiss_stale_reviews": true,
+        "require_code_owner_reviews": true
+      },
+      "restrictions": {
+        "users": [
+          "hollywood",
+          "primetheus"
+        ],
+        "teams": [
+          "test-team"
+        ]
+      }
+    }"""
+
+  stage("Protect Master Branch") {
+    if(env.branch_name && "${branch_name}" == "${master_branch}") {
+        // The credentialsId should match yours, not this demonstration
+        withCredentials([string(credentialsId: '1cf07897-ad01-4e59-9075-617ea40cf111', variable: 'githubToken')]) {
+          httpRequest(
+              contentType: 'APPLICATION_JSON',
+              consoleLogResponseBody: true,
+              customHeaders: [
+                  [maskValue: true, name: 'Authorization', value: "token ${githubToken}"],
+                  [name: 'Accept', value: 'application/vnd.github.loki-preview']],
+              httpMode: 'PUT',
+              ignoreSslErrors: true,
+              requestBody: githubPayload,
+              responseHandle: 'NONE',
+              url: "${repository_url}/branches/${repository_default_branch}/protection")
+        }
+    } else {
+        sh(name: "Skip", script: 'echo "Move along, nothing to see here"')
+    }
+  }
+}