added a few logos

Signed-off-by: Kai Kreuzer <kai@openhab.org>

_actions/tinkerforge/readme.md

@@ -6,6 +6,7 @@ type: action
 description: "The TinkerForge Action service provides direct interaction with some of the TinkerForge devices."
 source: https://github.com/openhab/openhab1-addons/blob/master/bundles/action/org.openhab.action.tinkerforge/README.md
 since: 1x
+logo: images/addons/tinkerforge.png
 install: manual
 ---
 

_bindings/sleepiq/readme.md

@@ -5,6 +5,7 @@ title: SleepIQ - Bindings
 type: binding
 description: "This binding integrates with the SleepIQ system from Select Comfort for Sleep Number beds."
 since: 2x
+logo: images/addons/sleepiq.png
 install: auto
 ---
 

_bindings/tankerkoenig/readme.md

@@ -5,6 +5,7 @@ title: Tankerkönig - Bindings
 type: binding
 description: "The binding uses the Tankerkönig API (https://www.tankerkoenig.de) for collecting gas price data of german gas stations."
 since: 2x
+logo: images/addons/tankerkoenig.png
 install: auto
 ---
 

_bindings/tinkerforge1/readme.md

@@ -6,6 +6,7 @@ type: binding
 description: "[TinkerForge](http://www.tinkerforge.com) is a system of open source hardware building blocks that allows you to combine sensor and actuator blocks by plug and play. You can create your individual hardware system by choosing the necessary building blocks for your project and combine it with other home automation products."
 source: https://github.com/openhab/openhab1-addons/blob/master/bundles/binding/org.openhab.binding.tinkerforge/README.md
 since: 1x
+logo: images/addons/tinkerforge.png
 install: auto
 ---
 

_bindings/tradfri/readme.md

@@ -5,6 +5,7 @@ title: Trådfri - Bindings
 type: binding
 description: "This binding integrates the IKEA Trådfri gateway and devices connected to it (such as dimmable LED bulbs)."
 since: 2x
+logo: images/addons/tradfri.png
 install: auto
 ---
 

_bindings/windcentrale/readme.md

@@ -5,6 +5,7 @@ title: Windcentrale - Bindings
 type: binding
 description: "This Binding is used to display the details of a Windcentrale windmill."
 since: 2x
+logo: images/addons/windcentrale.png
 install: auto
 ---