Update README.md

Remove section on adding the `dorie` wrapper to the PATH variable
from the installation instructions.

README.md

@@ -145,14 +145,6 @@ If you installed [Anaconda](https://conda.io/docs/user-guide/install/download.ht
         HDF5_ROOT=/usr/local
 
     to the `CMAKE_FLAGS` in the call to `dunecontrol` above.
- 
-5. After a successful build you can call the `dorie` wrapper located in `dorie/build-cmake/bin` from anywhere on your machine, but it is more handy to add this location to your search path. You can add the directory to your `PATH` variable by calling
-
-        PATH=<path/to/>dorie/build-cmake/bin:$PATH
-
-    However, this will only last for your current terminal session. Another option is to add this path permanently in your shell configuration file.
-
-    **Installing DUNE and DORiE via `make install` into your usual work environment is strongly discouraged!**
 
 ### Experimental Features
 The local operator implementing Richards equation's discretization supports