Small refactoring for packer scripts

* Get rid of formula version variable and use MCP_VERSION instead
* Remove docker images pull
* Remove adding of jenkins theme b/c it's already inside docker image
* Move flag for jenkins in docker to /opt

Closes-task: #PROD-24048 (PROD:24048)
Change-Id: I41a1c4771d9cf890bd371264a35727ded6fc52a8
diff --git a/trymcp-day01-image/run.example.sh b/trymcp-day01-image/run.example.sh
index ef02872..92ad386 100755
--- a/trymcp-day01-image/run.example.sh
+++ b/trymcp-day01-image/run.example.sh
@@ -20,7 +20,6 @@
 export CLUSTER_MODEL="https://gerrit.mcp.mirantis.com/trymcp/drivetrain-model"
 export CLUSTER_MODEL_REF="master"
 export CLUSTER_NAME="try-mcp"
-export FORMULA_VERSION="proposed"
 export GIT_SALT_FORMULAS_SCRIPTS="https://gerrit.mcp.mirantis.com/salt-formulas/salt-formulas-scripts"
 export MCP_VERSION="proposed"
 export SALTSTACK_GPG="https://repo.saltstack.com/apt/ubuntu/16.04/amd64/2017.7/SALTSTACK-GPG-KEY.pub"
diff --git a/trymcp-day01-image/scripts/salt.sh b/trymcp-day01-image/scripts/salt.sh
index ed696f4..2161aaf 100644
--- a/trymcp-day01-image/scripts/salt.sh
+++ b/trymcp-day01-image/scripts/salt.sh
@@ -1,7 +1,7 @@
 #!/bin/bash -xe
 
-FORMULA_VERSION=${FORMULA_VERSION:-2018.3.1}
-APT_MIRANTIS_SALT_REPO=${APT_MIRANTIS_SALT_REPO:-"http://apt.mirantis.com/xenial/ $FORMULA_VERSION salt"}
+MCP_VERSION=${MCP_VERSION:-proposed}
+APT_MIRANTIS_SALT_REPO=${APT_MIRANTIS_SALT_REPO:-"http://apt.mirantis.com/xenial/ $MCP_VERSION salt"}
 SALT_OPTS="-t 10 --retcode-passthrough --no-color"
 
 echo "deb [arch=amd64] ${APT_MIRANTIS_SALT_REPO}" > /etc/apt/sources.list.d/mcp_salt.list
diff --git a/trymcp-day01-image/template.json b/trymcp-day01-image/template.json
index aa63016..84f0a8e 100644
--- a/trymcp-day01-image/template.json
+++ b/trymcp-day01-image/template.json
@@ -10,7 +10,6 @@
     "cluster_model_ref": "{{ env `CLUSTER_MODEL_REF` }}",
     "cluster_name": "{{ env `CLUSTER_NAME` }}",
     "bs_hostname": "cfg01",
-    "formula_version": "{{ env `FORMULA_VERSION` }}",
     "mcp_version": "{{ env `MCP_VERSION` }}",
     "ubuntu_baseurl": "{{ env `UBUNTU_BASEURL` }}",
     "saltstack_gpg": "{{ env `SALTSTACK_GPG` }}",
@@ -54,7 +53,6 @@
         "CLUSTER_MODEL_REF={{ user `cluster_model_ref` }}",
         "CLUSTER_NAME={{ user `cluster_name` }}",
         "BS_HOSTNAME={{ user `bs_hostname` }}",
-        "FORMULA_VERSION={{ user `formula_version` }}",
         "SALTSTACK_GPG={{ user `saltstack_gpg` }}",
         "SALTSTACK_REPO={{ user `saltstack_repo` }}",
         "APT_MIRANTIS_GPG={{ user `apt_mirantis_gpg` }}",
@@ -62,7 +60,6 @@
         "GIT_SALT_FORMULAS_SCRIPTS={{ user `git_salt_formulas_scripts` }}",
         "APT_REPOSITORY={{ user `apt_repository` }}",
         "APT_REPOSITORY_GPG={{ user `apt_repository_gpg` }}",
-        "FORMULA_VERSION={{ user `formula_version` }}",
         "APT_MIRANTIS_SALT_REPO={{ user `apt_mirantis_salt_repo` }}",
         "BOOTSTRAP_SALTSTACK_COM=file:///opt/bootstrap.saltstack.com.sh",
         "MCP_VERSION={{ user `mcp_version` }}",