ENH: Structure formation probe and Density Profile

Initial commit to the repository which consists of:
(1) Structure Formation probe based on template tesselations
(2) Density profile VTK filter to interactively create density profile
plots.
ENH: Cleaning up master repository
COMP: Ignore .git subdirectory

Fixed build s.t. ".git" sub-diretory is ignored.
ENH: Interactive DensityProfile PV plugin

Added a paraview filter that allows the user to interactively
inspect a particle dataset and plot a density profile (i.e.,
the number of particles within a region). The user picks a
center, a sphere radius and the number of concentric spheres
to generate. For each sphere, the number of particles is
computed. When running in parallel, each process computes the
number of particles within each sphere independently and the
final results are sum-reduced to process 0 which is responsible
for generating the final table. In the present implementation the
overlap should be set to 0, i.e. no ghost cells to guarrantee
correctness.
ENH: Adding halofinder module

Adding halofinder, currently consisting of the cosmohalo code,
initially developed at LANL.
ENH: Initial PV plugin of halo-finder

The halo-finder will probably need to be broken up to
separate filters, for the FOF halo-finder and the SOD
finder.
ENH: Legacy cosmo reader
ENH: Change namespace to cosmologytools
COMP: Resolve minor linking issues
ENH: Initial commit of interfaces
COMP: Fix pointer arithmetic on void*

Fix compilation error due to pointer arithmetic on void*. Since
the size of void* is not known, older gcc compilers do not allow
you to increment it. This was fix by doing a reinterpet_cast to
a char*.
COMP: Specify MPI_LIBRARIES when linking
ENH: Initialize halofinder in constructor
COMP: Fix minor build issues
ENH: Change project/pv-plugins name
ENH: Rename HACCTools.xml to CosmologyTools.xml
ENH: Fortran interface updates

Updates to the Fortran interface as well as proper linking
with required libs etc.
ENH: Density Profile of FOF Centers (Part 1)

Initial changes to the density profile to allow calculation
of the profile at FOF centers. The user controls whether or
not to interactively pick the center or to use the FOF centers
for computing a density profile via a checkbox in the filter's
properties panel. Internally, the code was modified s.t. it
operates on an array of SphereCenters. When interactive there
is only a single SphereCenter which the user has access to control
and move about the domain. Otherwise, when UseFOFCenters is ON,
the SphereCenters array is populated with FOF centers returned
from the FOF halo finder.
ENH: Density Profile of FOF Centers (Part 2)

Changed filter such that it has two input ports for its two possible
inputs. The first input is required and consists of the raw particles.
The second input is optional and consists of the pre-calculated FOF
centers. If the FOF centers are provided, then, the filter will generate
a profile for each FOF. Otherwise, the user has the ability to interactively
move the cursor to a desired center.
STYLE: Remove debug statements