Update Things.md in order to show exampels for file created things an… (#888)

* Update Things.md in order to show exampels for file created things and bridges
Signed-off-by: Juergen Baginski opus42@gmx.de (github: JueBag)

* Update configuration/things.md (Accept PR Suggestions)
Signed-off-by: Jerome Luckenbach <github@luckenba.ch>
Co-Authored-By: JueBag <opus42@gmx.de>

configuration/things.md

@@ -64,15 +64,23 @@ See the [configuration tutorial]({{base}}/tutorials/beginner/configuration.html)
 Things can also be defined manually by creating `.things` configuration text files.
 These files are stored in `$OPENHAB_CONF/things`.
 
-Benefits of defining Things, Items and other aspects of openHAB in configuration text files are, that they are statically defined, unambiguous, flexible and easy to backup and restore.
-The main downsides of configuration files are the effort needed to compose them and the probability for typing errors.
-
 The syntax for `.things` files is defined as follows (parts in `<..>` are required):
 
 ```xtend
 Thing <binding_id>:<type_id>:<thing_id> "Label" @ "Location" [ <parameters> ]
 ```
 
+The first keyword defines whether the entry is a bridge or a thing. 
+The next statement defines the UID of the thing which contains of the following three segments: `binding id`, `thing type id`, `thing id`. 
+So the first two segments must match to a thing type supported by a binding (e.g. `network:device` or `astro:moon`), whereas the thing id can be freely defined. 
+Optionally, you may provide a label in order to recognize it easily, otherwise the default label from the thing type will be displayed.
+
+To help organizing your things, you also may define a location (`Location` in the example above).
+
+Inside the squared brackets configuration parameters of the thing are defined. 
+The type of the configuration parameter is determined by the binding and must be specified accordingly in the DSL.
+
+
 **Examples:**
 
 ```xtend
@@ -90,7 +98,52 @@ Looking at the first example:
 - the physical location of the Thing is "Living Room"
 - the values inside the `[]` brackets are the Thing's configuration parameters, these are partly mandatory and optional
 
-Please check each individual binding's [documentation](/addons/#binding) for details on what and how to define Things using the `*.things` configuration text files.
+Please check each individual binding's [documentation](/addons/#binding) for details on what and how to define the Things configuration parameters (inside the `[]` brackets) using the `*.things` configuration text files.
+
+### Defining Bridges Using Files
+
+Bridges can be defined together with contained things. The following configuration shows the definition of a hue bridge with two hue lamps:
+
+```xtend
+Bridge hue:bridge:mybridge [ ipAddress="192.168.3.123" ] {
+	Thing 0210 bulb1 [ lightId="1" ]
+	Thing 0210 bulb2 [ lightId="2" ]
+}
+```
+
+Within the curly brackets things can be defined, that should be members of the bridge. 
+For the contained thing only the thing type ID and thing ID must be defined (e.g. 0210 bulb1). 
+So the syntax is `Thing <thingTypeId> <thingId> []`. 
+The resulting UID of the thing is `hue:0210:mybridge:bulb1`.
+
+Bridges that are defined somewhere else can also be referenced in the DSL:
+
+```xtend
+Thing hue:0210:mybridge:bulb (hue:bridge:mybridge) [lightId="3"]
+```
+
+The referenced bridge is specified in the parentheses. 
+Please notice that the UID of the thing also contains the bridge ID as third segment. 
+For the contained notation of things the UID will be inherited and the bridge ID is automatically taken as part of the resulting thing UID.
+
+**Example of a MQTT Bridge with Generic MQTT Things :**
+```xtend
+Bridge mqtt:broker:MyMQTTBroker [ host="192.168.178.50", secure=false, username="MyUserName", password="MyPassword"] {
+  Thing topic sonoff_Dual_Thing "Light_Dual" @ "Sonoff" {  
+    Channels:
+      Type switch : PowerSwitch1  [ stateTopic="stat/sonoff_dual/POWER1" , commandTopic="cmnd/sonoff_dual/POWER1", on="ON", off="OFF"]
+      Type switch : PowerSwitch2  [ stateTopic="stat/sonoff_dual/POWER2" , commandTopic="cmnd/sonoff_dual/POWER2", on="ON", off="OFF"]
+      Type string : Version [stateTopic="stat/sonoff_dual/STATUS2", transformationPattern="JSONPATH:$.StatusFWR.Version"]
+      }     
+  Thing topic sonoff_TH_Thing "Light_TH" @ "Sonoff" {
+    Channels:
+      Type switch : PowerSwitch  [ stateTopic="stat/sonoff_TH/POWER", commandTopic="cmnd/sonoff_TH/POWER", on="ON", off="OFF" ]
+      Type string : Version [stateTopic="stat/sonoff_TH/STATUS2", transformationPattern="JSONPATH:$.StatusFWR.Version"]
+      Type number : Temperature [stateTopic="tele/sonoff_TH/SENSOR", transformationPattern="JSONPATH:$.AM2301.Temperature"]
+      Type number : Humidity [stateTopic="tele/sonoff_TH/SENSOR", transformationPattern="JSONPATH:$.AM2301.Humidity"]
+   }
+}   
+```
 
 ### Linking Items