dot: --dot=B to use bullets for all automata but Büchi and co-Büchi

* src/twaalgos/dotty.cc: Add option 'B'.
* src/taalgos/dotty.cc: Ignore it.
* src/bin/common_aoutput.cc, src/bin/dstar2tgba.cc: Document it.
* wrap/python/spot.py (setup): Use it by default, and rewrite
the function to be a bit more flexible.
* wrap/python/tests/automata-io.ipynb, wrap/python/tests/automata.ipynb,
wrap/python/tests/piperead.ipynb, wrap/python/tests/randaut.ipynb,
wrap/python/tests/testingaut.ipynb: Use setup() everywhere.

wrap/python/tests/randaut.ipynb

@@ -1,7 +1,7 @@
 {
  "metadata": {
   "name": "",
-  "signature": "sha256:f4c7efdcb7b97c3b11c230a6b18c8e46c1708289918a5dd8df73fe6baae3c8f6"
+  "signature": "sha256:0282f226c25df3a47177f96c3d474c1f5191fa8f7d87a35445a3d0d978bb8e35"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -12,15 +12,9 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "import os\n",
       "from IPython.display import display, HTML\n",
-      "# Note that Spot (loaded by the kernel) will store a copy of\n",
-      "# the environment variables the first time it reads them, so\n",
-      "# if you change those variables, the new values will be ignored\n",
-      "# until you restart the kernel.\n",
-      "os.environ['SPOT_DOTEXTRA'] = 'size=\"5.4,5\" node[style=filled,fillcolor=\"#ffffaa\"] edge[arrowhead=vee, arrowsize=.7]'\n",
-      "os.environ['SPOT_DOTDEFAULT'] = 'rbcf(Lato)'\n",
-      "import spot"
+      "import spot\n",
+      "spot.setup(size='5.4,5')"
      ],
      "language": "python",
      "metadata": {},
@@ -2034,7 +2028,7 @@
        "output_type": "pyout",
        "prompt_number": 2,
        "text": [
-        "<IPython.core.display.HTML at 0x7f5ca02a7b70>"
+        "<IPython.core.display.HTML at 0x7fc4e010a6d8>"
        ]
       }
      ],