Add tags

Add tags to allow more granular tasks filtering.
Add generator script for MD formatted tags found.
Add docs for tags how-to.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

roles/bootstrap-os/tasks/bootstrap-coreos.yml

@@ -3,7 +3,7 @@
   raw: stat /opt/bin/.bootstrapped
   register: need_bootstrap
   ignore_errors: True
-
+  tags: facts
 
 - name: Bootstrap | Run bootstrap.sh
   script: bootstrap.sh
@@ -11,6 +11,7 @@
 
 - set_fact:
     ansible_python_interpreter: "/opt/bin/python"
+  tags: facts
 
 - name: Bootstrap | Check if we need to install pip
   shell: "{{ansible_python_interpreter}} -m pip --version"
@@ -18,6 +19,7 @@
   ignore_errors: True
   changed_when: false
   when: (need_bootstrap | failed)
+  tags: facts
 
 - name: Bootstrap | Copy get-pip.py
   copy: src=get-pip.py dest=~/get-pip.py

roles/bootstrap-os/tasks/bootstrap-ubuntu.yml

@@ -5,6 +5,7 @@
   raw: which python
   register: need_bootstrap
   ignore_errors: True
+  tags: facts
 
 - name: Bootstrap | Install python 2.x
   raw: apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y python-minimal
@@ -12,3 +13,4 @@
 
 - set_fact:
     ansible_python_interpreter: "/usr/bin/python"
+  tags: facts