further fixes to gsa testsuite; make gsa compatible with Linux

matlab/PosteriorIRF_core1.m

matlab/ReshapeMatFiles.m

matlab/dynare_identification.m

matlab/dynare_sensitivity.m

matlab/gsa/filt_mc_.m

matlab/gsa/gsa_plotmatrix.m

matlab/gsa/map_ident_.m

matlab/prior_posterior_statistics.m

matlab/prior_posterior_statistics_core.m

tests/gsa/ls2003.mod

tests/gsa/ls2003scr_mean.mat

tests/gsa/ls2003scr_mode.mat

tests/gsa/ls2003scr_results.mat