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.
There were two changes:
Additions to support some reversible reactions which have fractional
stoichiometries. These were not allowed previously. However, if
the species with fractional stoichiometries are in single-species
phases, this is ok, and actually necessary for some solid-phase
reactions.
Removed comments from DEBUG_MODE about about too high or low an activation
for electrode reactions.
