A network with a single reactor can be created with either:
ReactorNet({reactor}), i.e. a single element cell array
or, the new way:
ReactorNet(reactor)
These changes make it unnecessary to copy header files around during
the build process, which tends to confuse IDEs and debuggers. The
headers which comprise Cantera's external C++ interface are now in
the 'include' directory.
All of the samples and demos are now in the 'samples' subdirectory.
