Initial pass at event decorators

Created event decorators for custom components. Decorators were created
for the events: track_state_change, track_sunrise, track_sunset, and
track_time_change.

homeassistant/bootstrap.py

@@ -24,6 +24,7 @@ import homeassistant.config as config_util
 import homeassistant.loader as loader
 import homeassistant.components as core_components
 import homeassistant.components.group as group
+from homeassistnat.helpers import event_decorators
 from homeassistant.helpers.entity import Entity
 from homeassistant.const import (
     __version__, EVENT_COMPONENT_LOADED, CONF_LATITUDE, CONF_LONGITUDE,
@@ -203,6 +204,9 @@ def from_config_dict(config, hass=None, config_dir=None, enable_log=True,
     for domain in loader.load_order_components(components):
         _setup_component(hass, domain, config)
 
+    # activate event decorators
+    event_decorators.activate(hass)
+
     return hass