Windows: Fix EOSdash startup Closes #436 #447 (#450)

* On Windows use 127.0.0.1 as default config host (model defaults) and
   addionally redirect 0.0.0.0 to localhost on Windows (because default
   config file still has 0.0.0.0).
   Use 0.0.0.0 as default otherwise (e.g. Linux/Docker) to allow EOS
   being accessible on local network (not just same host).
   Note: Docs generation on Windows is incompatible with the Github
   pipeline tests. Address this in the nested-config feature branch.
 * Update install/startup instructions as package installation is
   required atm and Docker on Windows has to be accessed at localhost or
   127.0.0.1 even though the server log says 0.0.0.0 (which is required
   to be available outside the container).
 * Fix EOSdash startup with read_only: true (support session key via
   EOS_SERVER__EOSDASH_SESSKEY variable). Backport of feature branch.
 * Remove root_path, causing Windows to fail load swagger UI (/docs).

docs/develop/getting_started.md

@@ -19,6 +19,7 @@ Install the dependencies in a virtual environment:
 
         python -m venv .venv
         .venv\Scripts\pip install -r requirements.txt
+        .venv\Scripts\pip install -e .
 
   .. tab:: Linux
 
@@ -26,6 +27,7 @@ Install the dependencies in a virtual environment:
 
         python -m venv .venv
         .venv/bin/pip install -r requirements.txt
+        .venv/bin/pip install -e .
 
 ```