docs code block formatting

`console` type code-block is designed mainly for examples of the console commands with the output.

If it's just a shell script with comments, then `console` only gets in the way - e.g. if you try to select a console code block manually, you won't be able to select comment symbol `#` at the beginning of the command making code unrunnable if you try to copy and run it. I've replaced it with `bash` or `bat` (for Windows) code blocks where `console` wasn't necessary.

I've also removed `$` symbols at the beginning of the commands if it's not a `console` code-block - since otherwise it just breaks "Copy Code Block" because you copy unrunnable code.

src/blenderbim/docs/users/advanced/dealing_with_large_models.rst

@@ -185,7 +185,7 @@ You can automate model processing using this command (~5% speedup):
 
 .. code-block:: bash
 
-    $ blender -b -P headless_import.py
+    blender -b -P headless_import.py
 
 The ``headless_import.py`` script contains instructions on how to configure
 model loading settings.