Fix the packer script that provisions jenkins workers

Selectively copy playbook dirs to avoid broken links
Install git in packer script so that the edx ansible fork can be installed via requirements.txt

util/packer/jenkins_worker.json

@@ -21,17 +21,32 @@
   }],
   "provisioners": [{
     "type": "shell",
-    "inline": ["rm -rf {{user `playbook_remote_dir`}}"]
+    "inline": ["rm -rf {{user `playbook_remote_dir`}}",
+      "mkdir {{user `playbook_remote_dir`}}"]
+  }, {
+        "type": "file",
+        "source": "../../playbooks/run_role.yml",
+        "destination": "{{user `playbook_remote_dir`}}/run_role.yml"
   }, {
     "type": "file",
-    "source": "../../playbooks",
-    "destination": "{{user `playbook_remote_dir`}}"
+    "source": "../../playbooks/roles",
+    "destination": "{{user `playbook_remote_dir`}}/roles"
+  }, {
+      "type": "file",
+      "source": "../../playbooks/edx-east",
+      "destination": "{{user `playbook_remote_dir`}}/edx-east"
   }, {
     "type": "file",
     "source": "../../requirements.txt",
     "destination": "{{user `playbook_remote_dir`}}/requirements.txt"
   }, {
     "type": "shell",
+    "inline": ["sudo add-apt-repository ppa:git-core/ppa -y"]
+  }, {
+    "type": "shell",
+    "inline": ["sudo apt-get -y install git-core"]
+  }, {
+    "type": "shell",
     "inline": ["cd {{user `playbook_remote_dir`}}",
       "virtualenv packer-venv",
       ". packer-venv/bin/activate",