Add "Edit on Github" links to the documentation.
Move the edit-on-github link for API objects to be next to the [source] link
Merge pull request #6 from iguananaut/issue-347

Move the edit-on-github link for API objects to be next to the [source] ...
Add a way to exclude pages from having "edit this page on github" links.
Improve configuration parameters docstring.
Comments
Change "edit on github" version logic so it points to a branch
Implementation of relativistic species (photons, neutrinos) into
cosmology classes.

Add neutrinos and photons to cosmology classes using nuetrino
treatement from Komatsu et al. 2011 ApJS 180, 330 (the WMAP7
cosmology paper).

* Add parameters Tcmb0, Neff, and m_nu to all classes, with defaults.
* Add nu_relative_density fucntion to compute rho_nu / rho_gamma
* Update all efunc/inv_efunc calculations to include relativistic species
* Because specifying a flat cosmology is slightly tricker when there is
  a small non-zero Omega_rel, added a few Flat cosmologies to make things
  easier on the user (FlatLambdaCDM, FlatwCDM).
* Updated tests.
* Updated docs.

The new code is not tested in detail -- but the old tests have been
modified to work (since they all assumed Orel = 0.0).

The neutrino treatement is exact but assumes that all neutrino species
have the same mass.  For some high masses they aren't properly relativistic,
but in practice they will be so it seems convenient to include them
in Omega_relativistic (note that I don't call it Omega_radiation for this
reason).

It isn't totally clear what the best way to include relativistic species is.
There are a number of possibilities.

* Ignore neutrino masses, assume the normal number of neutrinos, and
  work purely with Omega_rad.  This is the simplest, but is rather limiting
  because it makes totally vanilla assumptions.
* Allow for neutrinos with masses, but use Omega parameters as much
  as possible.  This requires: Omega_photon, Omega_nu (the usual
  Omega_nu h^2 = \sum m_nu / 94 eV), N_eff (the effective number
  of nuetrino species), N_nu (the actual number of neutrino species).
  Note that N_eff != N_nu (and they can't be easily calculated from each
  other, although they don't differ by much).  Also note that this,
  the usual way Omega_nu is written, is very confusing because it
  virtually -never- actually corresponds to the contribution of neutrinos
  to the total energy density.  So it looks like an Omega_nu, but actually
  isn't.  Even for low mass neutrinos, Omega_relativistic != Omega_photon
  + Omega_nu if you write it this way, which is really confusing.
* Try to use observable parameters as much as possible;  These are
  Tcmb0, m_nu, and N_eff.  The advantage is that the paramaterization
  has 1) fewer parameters than the previous one because it relates
  better to the actual physics, and 2) it is more directly related to
  observables.  However, the parameterization may be a little less familiar.

The latter is used in this branch right now because it is simpler.
Note that all the parameters have reasonable defaults -- in fact, most
users never really need know they exist at all.
Removed massive nuetrinos, now only support massless ones.

* Parameters remain the same except that m_nu is removed
* Internal functions having to do with nuetrino masses removed
* Test cases added:
   ** A comparison with Ned Wright's Advanced Cosmological Calculator.
      Unfortunately, the NWACC isn't that accurate (and uses the
      wrong value of a_B), so the precision of this test is limited.
  ** A comparison with a numerical calculation using Mathematica,
      which is significantly more precise.
  ** A test against the special case of only Or and Om, which can
     be evaluated analytically for comparision.
* Documentation updated.

The code passes all tests having to do with the cosmology module,
and sphinx builds without complaint.
Minor doc fix for FLRW.Onu
Removed inaccurate entry from changelog

The besancon reader ended up in the astroquery package rather than core astropy, but the changelog was erroneous updated to say it was in the core.
fixed note directive in io.ascii docs
fixed indentation/spacing in table docstrings
fixed erroring parameter list docstring in io.ascii.ipac
fixed io.ascii.ipac docstring to interpret caveats correctly
missing spaces in NDData.add and NDData.subtract docstrings
Moved autosummary templates inside core package, and use inheritance to use them in the docs (this is to allow affiliated packages to inherit the templates without duplicating content)
Write out all DP keywords
Populate DPj.EXTVER keywords correctly. Set EXTVER of the WCSDVARR extensions through a method. (Pyfits does not pick up this keyword if the hdulist is created from scratch and the header updated to include EXTVER.)
Added DPj.NAXES kw to header. Added keyword comments. Passed a keyword argument 'minerr' to det2im correction as a control flag for whether to use the correction or not based on the maximum error of the correction.