add tui module and example, add contex manager cd and the method run_file in helper

import vendor modules only once during import

change text color for the method cad_wireframe in geometry_plot_pylab and add hide key

docs/build/html/_modules/index.html

@@ -50,6 +50,7 @@
 <li><a href="pylib/numerical/ode.html">pylib.numerical.ode</a></li>
 <li><a href="pylib/numerical/ode_model.html">pylib.numerical.ode_model</a></li>
 <li><a href="pylib/time_of_day.html">pylib.time_of_day</a></li>
+<li><a href="pylib/tui.html">pylib.tui</a></li>
 </ul>
 
           </div>