Code Salvage

- Integrated some code from the (soon to be obsolete) 2.0.0 branch,
  which is general in nature and will be needed.
- And the corresponding unit tests.

src/tests/.gitignore

@@ -1,26 +1,31 @@
-t.t
-t.benchmark.t
-tdb.t
-date.t
-duration.t
-text.t
-autocomplete.t
-seq.t
-att.t
-record.t
-stringtable.t
-nibbler.t
-subst.t
-filt.t
-cmd.t
-config.t
-util.t
-color.t
-list.t
-path.t
-file.t
-directory.t
-grid.t
-rx.t
-taskmod.t
 *.log
+att.t
+autocomplete.t
+cmd.t
+color.t
+config.t
+date.t
+directory.t
+duration.t
+file.t
+filt.t
+grid.t
+lisp.t
+list.t
+nibbler.t
+path.t
+record.t
+rectangle.t
+rx.t
+sensor.t
+seq.t
+stringtable.t
+subst.t
+t.benchmark.t
+t.t
+taskmod.t
+tdb.t
+text.t
+tree.t
+tree2.t
+util.t