Disable fparser debugging functions by default

And fix the fparser Makefile so that whether they're enabled will
depend correctly on the configure options
adding qhull
adding upstream Makefile
build Qhull as a contributed package
build Qhull programs and add them as a check target
descriptive comment about where the mysterious checks came from
Qhull does not install any headers, yet anyway.
avoid duplicate symbols in C++ library
adding CHANGES file to track changes
avoid unused variable warning
add new generated file
bootstrap
Adding ParsedFEMFunction subclass

This needs some work to handle vector-valued elements, but for now it
ought to be a decent way to give parsed functions in configuration
files access to your solution variables.
Allow FEMFunctionBase data in DirichletBoundary
Bugfixes for FEMFunctionBase dirichlet BCs
ParsedFEMFunction bugfixes
Update traffic.
Use libmesh_error_msg() where appropriate.
Use libmesh_error_msg() where appropriate.
Use libmesh_error_msg() where appropriate.