Use the home_assistant user for most tasks

This updates the formula to use the home_assistant user for tasks like
cloning the git repo and making the virtual environment. This allows
home assistant to perform some tasks it otherwise can't do due to
permission issues, like installing needed python libraries at runtime.

This also allows the ssh identity used for cloning the git repo to be
specified.

Signed-off-by: M. David Bennett <mdavidbennett@syntheticworks.com>

README.rst

           engine: git
           address: '${_param:home_assistant_config_repository}'
           branch: ${_param:home_assistant_config_revision}
+          identity: /path/to/optional/ssh/identity/file
 
 
 References

home_assistant/server.sls

   pkg.installed:
   - names: {{ server.pkgs }}
 
+home_assistant_user:
+  user.present:
+  - name: home_assistant
+  - system: true
+  - home: {{ server.dir.base }}
+
 {{ server.dir.base }}:
   virtualenv.manage:
+  - user: home_assistant
   - system_site_packages: True
   - requirements: salt://home_assistant/files/requirements.txt
   - python: /usr/bin/python3
   - require:
     - pkg: home_assistant_packages
+    - user: home_assistant_user
 
 home_assistant_install:
   pip.installed:
   {%- else %}
   - name: homeassistant{%- if server.get('source', {}).version is defined %}=={{ server.source.version }}{%- endif %}
   {%- endif %}
+  - user: home_assistant
   - pre_releases: True
   - bin_env: {{ server.dir.base }}
   - exists_action: w
     - virtualenv: {{ server.dir.base }}
     - pkg: home_assistant_packages
 
-home_assistant_user:
-  user.present:
-  - name: home_assistant
-  - system: true
-  - home: {{ server.dir.base }}
-  - require:
-    - virtualenv: {{ server.dir.base }}
-
 home_assistant_dir:
   file.directory:
   - names:
 home_assistant_config:
   git.latest:
   - name: {{ server.config.address }}
+  - user: home_assistant
   - target: /etc/home_assistant
   - rev: {{ server.config.revision|default(server.config.branch) }}
   {%- if grains.saltversion >= "2015.8.0" %}
   - branch: {{ server.config.branch|default(server.config.revision) }}
   {%- endif %}
+  {%- if server.config.identity is defined %}
+  - identity: {{ server.config.identity }}
+  {%- endif %}
   - force_reset: {{ server.config.force_reset|default(False) }}
 
 {%- else %}
 
-home_assistant_config_dir:
-  file.directory:
-  - name: /etc/home_assistant
-  - mode: 700
-  - makedirs: true
-  - user: home_assistant
-  - require:
-    - virtualenv: {{ server.dir.base }}
-
 home_assistant_config:
   file.managed:
   - name: /etc/home_assistant/configuration.yaml
   - user: home_assistant
   - mode: 600
   - require:
-    - file: home_assistant_config_dir
+    - file: home_assistant_dir
 
 {%- if server.known_device is defined %}