Remove outdated docs

doc/NEWS.txt

-.. _NEWS:
-
-.. include:: ../NEWS.txt

doc/citation.rst

-:orphan:
-
-.. _citation:
-
-
-Aesara Citation Policy
-======================
-
-If you use Aesara for academic research, you are highly encouraged (though not
-required) to cite the following paper:
-
-* Theano Development Team. `"Theano: A Python framework for fast computation of mathematical expressions"
-  <http://arxiv.org/pdf/1605.02688.pdf>`_.
-  (:download:`short BibTeX <theano-short.bib>`, :download:`full BibTeX <theano-full.bib>`)
-
-Earlier articles:
-
-* F. Bastien, P. Lamblin, R. Pascanu, J. Bergstra, I. Goodfellow,
-  A. Bergeron, N. Bouchard, D. Warde-Farley and Y. Bengio.
-  `"Theano: new features and speed improvements"
-  <http://arxiv.org/pdf/1211.5590.pdf>`_.
-  NIPS 2012 deep learning workshop. (`BibTeX
-  <http://www.iro.umontreal.ca/~lisa/publications2/index.php/export/publication/551/bibtex>`__)
-
-* J. Bergstra, O. Breuleux, F. Bastien, P. Lamblin, R.
-  Pascanu, G. Desjardins, J. Turian, D. Warde-Farley and Y.
-  Bengio. `"Theano: A CPU and GPU Math Expression Compiler"
-  <http://www.iro.umontreal.ca/~lisa/pointeurs/theano_scipy2010.pdf>`_.
-  *Proceedings of the Python for Scientific Computing Conference (SciPy)
-  2010. June 30 - July 3, Austin, TX* (`BibTeX
-  <http://www.iro.umontreal.ca/~lisa/publications2/index.php/export/publication/461/bibtex>`__)

doc/internal/dev_start_guide.rst

-.. _old_dev_start_guide:
-
-============================
-Developer Start Guide MOVED!
-============================
-
-
-The developer start guide :ref:`moved <dev_start_guide>`.

doc/internal/python.rst

-.. _python_booster:
-
-================
-Python booster
-================
-
-`This page
-<http://wordaligned.org/articles/essential-python-reading-list>`_ will
-give you a warm feeling in your stomach.
-
-Non-Basic Python features
--------------------------
-
-Aesara doesn't use your grandfather's python.
-
-  * properties
-
-    a specific attribute that has get and set methods which python automatically invokes.
-
-    See [http://www.python.org/doc/newstyle/ New style classes].
-  * static methods vs. class methods vs. instance methods
-  * Decorators:
-
-    .. code-block:: python
-
-      @f
-      def g():
-        ...
-
-    runs function ``f`` before each invocation of ``g``.
-    See `PEP 0318 <http://www.python.org/dev/peps/pep-0318/>`_.
-    ``staticmethod`` is a specific decorator, since python 2.2
-  *  ``__metaclass__`` is kinda like a decorator for classes. It runs the metaclass __init__ after the class is defined
-  * ``setattr`` + ``getattr`` + ``hasattr``
-  * ``*args`` is a tuple like argv in C++, ``**kwargs`` is a keyword args version
-  * ``pass`` is no-op.
-  * functions (function objects) can have attributes too. This technique
-    is often used to define a function's error messages.
-
-     >>> def f(): return f.a
-     >>> f.a = 5
-     >>> f()
-     5
-
-  * Warning about mutual imports:
-
-    * script a.py file defined a class A.
-    * script a.py imported file b.py
-    * file b.py imported a, and instantiated a.A()
-    * script a.py instantiated its own A(), and passed it to a function in b.py
-    * that function saw its argument as being of type __main__.A, not a.A.
-
-    Incidentally, this behaviour is one of the big reasons to put autotests in
-    different files from the classes they test!
-
-    If all the test cases were put into <file>.py directly, then during the test
-    cases, all <file>.py classes instantiated by unit tests would have type
-    ``__main__.<classname>``, instead of type ``<file>.<classname>``.  This should never
-    happen under normal usage, and can cause problems (like the one you are/were
-    experiencing).