Add 'packer-image-create' job

- add packer-image-create.groovy to create images with packer
- add 'tcp_tests/templates/_packer/' with configs for 'foundation'
  node

Change-Id: I23379bef389adad791df9343930095a57af3fb55
diff --git a/src/com/mirantis/system_qa/SharedPipeline.groovy b/src/com/mirantis/system_qa/SharedPipeline.groovy
index 5a78a9f..06ca19d 100644
--- a/src/com/mirantis/system_qa/SharedPipeline.groovy
+++ b/src/com/mirantis/system_qa/SharedPipeline.groovy
@@ -185,15 +185,18 @@
         """)
 }
 
-def update_working_dir() {
+def update_working_dir(Boolean updateRequirements=true) {
         // Use to fetch a patchset from gerrit to the working dir
         run_cmd("""\
             if [ -n "$TCP_QA_REFS" ]; then
                 set -e
                 git fetch https://review.gerrithub.io/Mirantis/tcp-qa $TCP_QA_REFS && git checkout FETCH_HEAD || exit \$?
-            fi
-            pip install -r tcp_tests/requirements.txt
-        """)
+            fi""")
+        if (updateRequirements) {
+            run_cmd("""\
+                pip install -r tcp_tests/requirements.txt
+            """)
+        }
 }
 
 def swarm_bootstrap_salt_cluster_devops() {