Conflicts:
	moose-core/CMakeLists.txt

portable solution.

Script creates a test model of a dendrite segment with one Ca
channel. DifShells are created. DifBuffers are created. DifShells are
connected to provide diffusion. DifBuffers are connected to provide
diffusion. DifBuffers are connected with DifShells to provide
buffer. MMPumps are created and connected to the outer DifShell. Ca
channel is connected to the outer Difshell to provide Ca influx and
outer DifShell is connected to Ca channel to provide ion
concentration. Segment's Vm, channel's Gk and Ik, DifShell's C and
DifBuffer's bBound are connected with output to save simulation
results.

Make sure that innerArea is not negative. Move sending out of messages
to the bottom of the process function. Add sending out of
concentration to the buffer and diffusion to other difshells in
DifShell and diffusion to other buffers in DifBuffer in reinit. This
matches genesis implementation.

In DifShell reinit set C (calcium) to Ceq. In DifBuffer reinit
calculate bFree (free buffer) and bBound (bound buffer) to steady
state value. This matches genesis implementation.

Integration results were incorrect, because the helper variables were
not reset after every iteration.

Most of Cinfo code is moved to DifShellBase, so it got deleted from
DifShell. Method's names are changed, because they are now inherited
from DifShellBase.

Base classes are necessary for implementing hsolve.

Reintroduced implementation of Difbuffer used moose objects that have
been since rewritten and renamed.  Change used moose objects to
current version.

Change process_0 to proc, to match other classes which need to be
driven by ticks.

π is defined as a constant in the headers, no need to create a
variable. Also constify some other variables. No functional change.

New getters and setters are added.