render_with_collect method for template (#23283)

* Make entity_filter be a modifiable builder

* Add render_with_collect method

* Use sync render_with_collect and non-class based test case

* Refactor: Template renders to RenderInfo

* Freeze with exception too

* Finish merging test changes

* Removed unused sync interface

* Final bits of the diff

homeassistant/helpers/config_validation.py

@@ -23,7 +23,6 @@ from homeassistant.const import (
     TEMP_CELSIUS, TEMP_FAHRENHEIT, WEEKDAYS, __version__)
 from homeassistant.core import valid_entity_id, split_entity_id
 from homeassistant.exceptions import TemplateError
-from homeassistant.helpers import template as template_helper
 from homeassistant.helpers.logging import KeywordStyleAdapter
 from homeassistant.util import slugify as util_slugify
 
@@ -445,6 +444,8 @@ unit_system = vol.All(vol.Lower, vol.Any(CONF_UNIT_SYSTEM_METRIC,
 
 def template(value):
     """Validate a jinja2 template."""
+    from homeassistant.helpers import template as template_helper
+
     if value is None:
         raise vol.Invalid('template value is None')
     if isinstance(value, (list, dict, template_helper.Template)):