Revamp README to better advertise capabilities

README.rst

@@ -1,5 +1,5 @@
-modepy: Basis Functions and Node Sets for Interpolation
-=======================================================
+modepy: Basis Functions, Node Sets, Quadratures
+===============================================
 
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@@ -18,12 +18,41 @@ modepy: Basis Functions and Node Sets for Interpolation
 simplices (i.e. segments, triangles and tetrahedra) and tensor products of
 simplices (i.e. squares, cubes, prisms, etc.). These are a key building block
 for high-order unstructured discretizations, as often used in a finite
-element context. It closely follows the approach taken in the book
+element context. Features include:
+
+- Support for simplex and tensor product elements in any dimension.
+- Orthogonal bases:
+    - Jacobi polynomials with derivatives
+    - Orthogonal polynomials for simplices up to 3D and tensor product elements
+      and their derivatives.
+    - All bases permit symbolic evaluation, for code generation.
+- Access to numerous quadrature rules:
+    - Jacobi-Gauss, Jacobi-Gauss-Lobatto in 1D
+      (includes Legendre, Chebyshev, ultraspherical, Gegenbauer)
+    - Clenshaw-Curtis and Fejér in 1D
+    - Grundmann-Möller on the simplex
+    - Xiao-Gimbutas on the simplex
+    - Vioreanu-Rokhlin on the simplex
+    - Jaśkowiec-Sukumar on the tetrahedron
+    - Witherden-Vincent on the hypercube
+    - Generic tensor products built on the above, e.g. for prisms and hypercubes
+- Matrices for FEM, usable across all element types:
+    - generalized Vandermonde,
+    - mass matrices (including lumped diagonal),
+    - face mass matrices,
+    - differentiation matrices, and
+    - resampling matrices.
+- Objects to represent 'element shape' and 'function space',
+  generic node/mode/quadrature retrieval based on them.
+
+Its roots closely followed the approach taken in the book
 
   Hesthaven, Jan S., and Tim Warburton. "Nodal Discontinuous Galerkin Methods:
   Algorithms, Analysis, and Applications". 1st ed. Springer, 2007.
   `Book web page <http://nudg.org>`_
 
+but much has been added beyond that basic functionality.
+
 Resources:
 
 * `documentation <http://documen.tician.de/modepy>`_