ENH: Update anatomical coregistration defaults, purge unused file

Author: mgxd

nibabies/data/within_subject_t1t2.json renamed to nibabies/data/t1-t2-coreg.json

@@ -31,9 +31,9 @@
     [ 0.1, 3.0, 0.0 ]
   ],
   "transforms": [ "Translation", "Rigid", "SyN" ],
-  "use_histogram_matching": [ true, true, true ],
+  "use_histogram_matching": false,
   "verbose": true,
   "winsorize_lower_quantile": 0.0001,
   "winsorize_upper_quantile": 0.9999,
-  "write_composite_transform": false
+  "write_composite_transform": true
 }