Description: This patch adds interpolation routines to CosmoMC (May
2010 release) for computing the likelihood, r10, and sigma_8 values.

Installing the patch:
 - run 'patch --dry-run -p1 -i interp.patch' 
[Check to make sure things are OK before applying the patch.]
 - run 'patch -p1 -i interp.patch'
 - run 'make' in source subdirectory

Before running CosmoMC, be sure to add to the params.ini file:
 - cut = sets cut for the difference from min likelihood to determine
   whether the interpolated likelihood is used.
 - factor = factor to multiply the number of terms in the
   polynomial. Once the chain has collected this number of points for
   the interpolation it will begin.
 - interp_order = sets the minimum order for the interpolation
 - do_interp = flag for whether to use the interpolation routines.
 - fraction_cut = sets fractional cut fur using the interpolation
   (compare different order interpolated values.)

Note: The order of the r10 interpolation is set at 2.

Description of changed or added files:

lsq.f90 (new) 
 -contains least-squares routines. Source code from Alan Miller's
  software page: http://users.bigpond.net.au/amiller/.

interpolation.f90 (new)
 -contains interpolation routines.

MCMC.f90 
 -adds variables 
 -computes the number of parameters (e.g. # of terms in the
  polynomial) for the interpolation
 -write some information to the logfile 
 -stores likelihoods computed with CAMB
 -initializes exponent array used for calculating interpolated values.
 -calls AddMPIParams(CurParams%P,CurLike) 
!INTERPOLATION CALL IS IN PARAMDEF.F90 to do the interpolation (when
 CosmoMC normally checks for convergence)

paramdef.F90 
 -calls interpolation routine forMPI versions when CosmoMC checks
  convergence statistics.
 -shares the local number of accepted points across the chains. Once
  the total number of accepted points exceeds thresh_val, then the
  interpolation function is calculated using previously calculated
  likelihoods.

driver.F90
 - variable 'numtoget' is added to settings.f90 so it can be accessed by
 MCMCsample routine
 - logical variable mpk_ind is set use_mpk value. Determines whether
 sigma_8 is included in the interpolation.
 -reads in thresh_val, interp_order, cut, and do_interp from .ini file 
 -settings.f90
 -Adding global variables (specifically):
   -databases for points used to calculate the likelihood
   -Coefficient arrays
   -Exponent arrays
   -Number of terms in the polynomials.  

params_CMB.f90
 -Changed writing routine for r10 to include interpolated r10 value.
 
 11/28/10