Provide data to integration test.

This test, which is not run by the testsuite, fails.

tests/analytic_derivatives/ls2003.mod

@@ -61,6 +61,6 @@ stderr e_ys,inv_gamma_pdf,1.2533,0.6551;
 stderr e_pies,inv_gamma_pdf,1.88,0.9827;
 end;
 
-estimation(datafile=data_ca1,first_obs=8,nobs=79,mh_nblocks=2,
+estimation(datafile='../ls2003/data_ca1.m',first_obs=8,nobs=79,mh_nblocks=2,
    prefilter=1,mh_jscale=0.5,mh_replic=0, mode_compute=1, analytic_derivation);