Merge tag 'v3.0' into develop

A major release that improves performance.

setup.py

@@ -4,7 +4,7 @@ from setuptools import setup, find_packages
 
 
 setup(name='hdpg1d',
-      version='2.0',
+      version='3.0',
       description='An 1D finite element solver using hybridizable discontinuous\
       Petrov-Galerkin method',
       author='Keyi Ni',