Updates the README to mention config parameters.

README.md

@@ -1,6 +1,7 @@
 # partkeepr docker image
 
-This is the source repository for the trusted builds of the [`mhubig/partkeepr`][0] docker image releases. For more information on PartKeepr check out the [website][1].
+This is the source repository for the trusted builds of the [`mhubig/partkeepr`][0]
+docker image releases. For more information on PartKeepr check out the [website][1].
 
 > The most resent version is: 1.4.0-15
 
@@ -21,7 +22,11 @@ export PARTKEEPR_OKTOPART_APIKEY=0123456
 docker-compose up
 ```
 
-Now go to the partkeepr setup page (e.g.: http://localhost/setup) and follow the directions. To get the authentikation key you can use something like:
+> To get a list of all supported environmnet variables go to the file [`mkparameters`][3],
+> starting at line 15.
+
+Now open the partkeepr setup page (e.g.: http://localhost/setup) and follow the
+directions. To get the generated authentikation key you do something like this:
 
 ```shell
 docker exec -it partkeepr cat app/authkey.php
@@ -45,7 +50,8 @@ docker build -t mhubig/partkeepr:latest --rm .
 
 ## Howto create a new release
 
-Since I have switched to [GitHub Flow][3], releasing is now quite simple. Ensure you are on master, bump the version number and push:
+Since I have switched to [GitHub Flow][4], releasing is now quite simple.
+Ensure you are on master, bump the version number and push:
 
 ```shell
 ./bump-version.sh 1.4.0-15
@@ -54,9 +60,12 @@ git push && git push --tags
 
 ## Docker Image CI/CD Pipeline
 
-This git repo is connected to a build Pipeline on https://hub.docker.com. A new Image is build for every Tag pushed to this repo. The images are taged with a version number (e.g. `1.4.0-15`) and `latest`.
+This git repo is connected to a build Pipeline on https://hub.docker.com. A new
+Image is build for every Tag pushed to this repo. The images are taged with a
+version number (e.g. `1.4.0-15`) and `latest`.
 
 [0]: https://hub.docker.com/r/mhubig/partkeepr/
 [1]: http://www.partkeepr.org
 [2]: https://www.docker.com
-[3]: https://guides.github.com/introduction/flow/
+[3]: https://github.com/mhubig/docker-partkeepr/blob/master/mkparameters#L15
+[4]: https://guides.github.com/introduction/flow/