[QNAP] Add installation instructions (openhab#220)

* Initial instructions for QNAP

Basically copy/pasted from openhab-qnap-qpkg/README.md

Relates to: openhab/openhab-docs#201
Signed-off-by: Thomas Karl Pietrowski <thopiekar@gmail.com> (github: thopiekar)

* Update qnap.md

Signed-off-by: Thomas Dietrich <thomas.dietrich@tu-ilmenau.de> (github: ThomDietrich)

* Remove scaling again

Signed-off-by: Thomas Dietrich <thomas.dietrich@tu-ilmenau.de> (github: ThomDietrich)

installation/qnap.md

@@ -10,4 +10,43 @@ title: QNAP NAS
 The [QNAP NAS](https://www.qnap.com) is a NAS server solution for your home, allowing the installation of additional packages.
 Download the latest openHAB package for QNAP from [here](https://github.com/openhab/openhab-qnap-qpkg).
 
-{% include contribution-wanted.html %}
+![AppCenter enabled](https://github.com/openhab/openhab-qnap-qpkg/raw/master/docs/QTS_4.2.0_AppCenter%20enabled.png)
+
+## How to install
+1. Download the QPKG from the [releases section over on GitHub](https://github.com/openhab/openhab-qnap-qpkg/releases).
+
+2. Create a directory for your addons, configurations and userdata, by
+
+  1. Creating a share called "openHAB2" (recommended)
+  2. Creating folder called "openHAB2" in "Public" share
+  3. Not creating any of them and therefore using ".qpkg/openHAB2/distribution" for all data (for testing or demonstration)
+
+3. Go to your NAS's App Center and make sure you have got "JRE" (for x86) or "JRE_ARM" (for ARM) installed. You can find the application via search function or under the category "Developer Tools".
+
+4. Wait for a while until the Java installation has finished.
+
+5. Open the "Install manually" dialog and choose the qpkg you have downloaded
+
+  ![AppCenter choose](https://github.com/openhab/openhab-qnap-qpkg/raw/master/docs/QTS_4.2.0_AppCenter%20choose.png)
+
+6. Confirm the installation 
+
+  ![AppCenter confirm](https://github.com/openhab/openhab-qnap-qpkg/raw/master/docs/QTS_4.2.0_AppCenter%20confirm.png)
+
+7. Wait while the package is being installed
+
+  ![AppCenter installing](https://github.com/openhab/openhab-qnap-qpkg/raw/master/docs/QTS_4.2.0_AppCenter%20installing.png)
+
+8. When finished just close the dialog and wait for a while until openHAB has completly started.
+
+  ![AppCenter finished](https://github.com/openhab/openhab-qnap-qpkg/raw/master/docs/QTS_4.2.0_AppCenter%20finished.png)
+
+9. Access openHAB via [http://NAS_IP_or_DNS_address:8090](#)
+
+## How to uninstall
+1. Go to the "App Center" and remove the app like any other.
+2. If wanted/needed also remove "addons", "conf" and "userdata" from the your directory, eg. "openHAB2" share or "Public"/openHAB2
+  * _REMEMBER_: If you have installed openHAB2 to ".qpkg" (see "How to install", section 2.3) then all files get removed directly!
+
+## Known issues
+* Please check our issue tracker: https://github.com/openhab/openhab-distro/issues