Major refactoring. Changes to movie search, movie forms implemented, shortlist started

Major refactoring, code is now divided up amongst specific user controls
sorted into folders. Code is no longer a single monolithic mess kept in
Form1.cs.

- Movie search can now filter results on director and actors.
- If either field is left empty then movies will not be filtered by
actors or director.
- Actor search filters out movies that have ALL of the actors specified.
User provides data through comma-separated strings in a RichTextBox.
- Director search matches the query to the movie's director property.

- Clicking on a MovieBox in MovieBoxPanel now opens a form displaying
more information on that movie. Presently only one of such windows can
be open at once and takes focus form the MainForm.
- Users can add movies to their Short List from this form.

- Shortlist implemented as a local variable of MovieTabPanel.
- Holds a list of Strings.
- Users can drop-and-drop MovieBoxes or add movies through the
MovieForms.

REMAINING ISSUES
- GenreCheckedList defaults to having no genres selected and thus the
initial search provides no data.
- Genre search will be changed so that having no genres selected does
not filter movies on genre.
- Deselect all/Clear option would be helpful for GenreCheckedList.