structure names (?!).

Default change: no longer skip blank times!
Per-data time ranges now extend overall clock range,
don't replace it.
Reset material properties (shininess, specular, ambient)
when drawing a lighted mesh.

used if --with-model.

rdata/readpath command uses originating filename for path search.

path searching.

"where" command gives full-precision values, and reports jump-pos with scale.
Allow for model-specific render function (initially for Maya models).
env TXDEBUG.