pep8 E261
pep8 E262
pep8 E271
pep8 E272
pep8 E301
pep8 E302
pep8 E303
pep8 E401
pep8 E502
pep8 E701
pep8 E702
pep8 E711
pep8 E721
galgebra: remove duplicate if-block
pep8 E501
pep8 E501: doctest output (manual)

Wrapping long docstring output appears to currently follow
these rules

    don't break within brackets unless they are tuple/list/dict-type or
    have a comma

        NO:

        >>> a*(a*b + c)
        a*(
        a*b + c)
        >>> a*(a*b + c)
        a*(a*
        b + c)

        YES:

        >>> [a, b, c]
        [a,
        b, c]
        >>> f(a, b)
        f(a,
        b)

    don't break after `/` or `*` but you can break after `+` or `-`:

        NO:

        >>> a*(a*b + c)
        a*(a*
        b + c)

        YES:

        >>> a*(a*b + c)
        a*(a*b +
        c)
pep8 E501: doctest input (manual)

The current rules for breaking input within docstrings appear to be:

docstring imports
    if the list of things being imported are not in parentheses then
       use \ at the end
           >>> import a, b, c, \
           ...        d, e
           >>> import (a, b, c,
           ...         d)
    whether there are parentheses or not, continue with ...

docstring input
    to continue an input, use \ if you are not inside
        a bracket when entering the new line and use ..., otherwise
        (if in a bracket) you don't need the \ but do need the ...
        >>> y = a*(
        ... b + c)
        a*(b + c)
        >>> y = a*\
        ... (b + c)
        a*(b + c)

    There seems to be some deviations from this rule, however. This

        >>> y = a*b + c + \
                b*a

    generates

            y = a*b + c + \
                      ^
        SyntaxError: unexpected EOF while parsing

   and is corrected by putting ... to start the 2nd line.

   On the other hand,

       >>> non_trivial_metric = exp(2*R2.r)*TP(R2.dr, R2.dr) + \
                                R2.r**2*TP(R2.dtheta, R2.dtheta)

   does not raise an error unless you add the ..., so

       >>> non_trivial_metric = exp(2*R2.r)*TP(R2.dr, R2.dr) + \
       ...                      R2.r**2*TP(R2.dtheta, R2.dtheta)

   generates

           non_trivial_metric = exp(2*R2.r)*TP(R2.dr, R2.dr) +     ...                   R2.r**2*TP(R2.dtheta, R2.dtheta)
                                                                ^
        SyntaxError: invalid syntax
Fix IPython printing extension
pep8 E225 around OP with = (manual)
Fix typos in aboutus.rst.