plot functions now pass on kwargs when constructing series.
Added `to_matrix` method to Vector and Dyadic in mechanics.

When jumping back and forth from symbolics to numerics when using the mechanics
module it would be nice to be able to output the matrix forms of vectors and
dyadics with respect to different reference frames. I've added two new methods
that provide this functionality. It is particularly useful for returning
inertia tensors in reference frames from dyadics as the tensor form in the more
widely used.
Changed syntax on the doc test so it now passes.
Added links to missing docs in RST file for the diffgeom module
Better docs for Subs.

- Added examples to resolve confusion regarding the result of subs and the limiting value of the expression at that point
- Added examples to clearly show the difference between substitution and numerical evaluation.
- Added `evalf` in the `See Also` of `Subs` documentation section.
minor doc fix
Merge pull request #2688 from Upabjojr/diffgeom_doc

Added links to missing docs in RST file for the diffgeom module
gh2666: terms_gcd does not remove and _keep_coeff doesn't hold 1.0

In addition, if only a 1 (or 1.0) is extracted, the original
expression is returned from terms_gcd rather than the polys-modified
form (e.g. 2.0*x + 3 instead of 2.0*x + 3.0).
edit fancysets docstrings
Solvers: removed duplicate output

Fixes issue 4129 by passing result through set before returning
Merge pull request #2649 from hargup/fix_subs_doc

Better docs for Subs.
Merge pull request #2674 from smichr/fancy

edit fancysets docstrings
Corrected position of ordered and set tomaintain canonical ordered list
Simplified the code with list comprehensions.
Added notes in documentation about .
Added test cases for issue 4129
Removed redundant test cases
fix generate_bell with recursive algorithm

TODO: replace with a non-recursive algorithm.
Document mathematical constants singletons
Standard reference for NaN