The E-Table package implements an editable table that provides
user-defined rendering, user-defined editing, sorting and grouping of
the objects displayed.

It is inspired by Java's Swing JTable object.  There are models for
the actual table contents and for the table headers; they are the
actual repository of information.

The objects are rendered by various view objects.  In the current code
base, we use we use GnomeCanvasItems to do the rendering.  One for
each table and one for the headers.

* The main widget

e-table.c, e-table.h:

	Implements a full widget.  Uses various components described
	below.  Handles column display as well as grouping/nesting

* The Models

All of them are GtkObjects.

e-table-model.h, e-table-model.c:

	These implement the abstract E-Table-Model class.  You
	can derive this object to create your own data repository.

	These emits signals to notify the views about selection, and
	changes in the model.

e-table-simple.h, e-table-simple.c:

	A simple implementation of e-table-model that uses callback
	routines (you provide the callbacks).  For lazy people, like
	me. 

e-cell.c, e-cell.h:

	These are actually mis-named.  Objects of type e-cell know
	about rendering a single cell, and these are attached to the
	e-table-cols (described next).

	The user provides the various rendering modes as e-cells (they
	are actually column-rendering repositories).

	This is just an abstract class.  I will provide various
	e-cells: a text cell, a checkbox cell, an image cell, and
	perhaps an n-state image cell (one that switches the image when
	the cell is clicked). 

e-table-col.h, e-table-col.c:

	Describes a single column (the size, the string displayed, the
	rendering function for each row and comparison function for
	this field).


* The Views

e-table-header.h, e-table-header.c:

	These implement the ETableHeaderItem canvas item.  This item is
	used both to control the columns displayed as well as displaying them. 

	They describe what columns are shown in the screen and in
	which order.

	These emit signals: column-size-changed and structure-changed
	(if a column is added/removed)

e-table-item.c, e-table-item.h

	This is a canvas item that renders the contents of a
	ETableModel into the screen.

e-table-header-item.c, e-table-header-item.h

	This canvas item renders the ETableHeader headings.

e-cell-text.c, e-cell-text.h

	Not really a view, but actually a derivative of e-cell that
	implements text display: supports justification and font
	setting.  Will add color in the future most likely

e-cell-toggle.c, e-cell-toggle.h

	A derivative of e-cell as well that support N-toggle values
	using images.

e-cell-check.c, e-cell-check.h
	
	An e-cell-toggle with two states only (for checkboxes).

* The Filters

e-table-sorted.c, e-table-sorted.h

	This is an ETableModel that can sort an existing ETableModel.

e-table-subset.c, e-table-subset.h

	Not finished, but it is just an ETableModel that happens to be
	a subset of another ETableModel.

* Everything

e-table.c, e-table.h

	In the future these guys will implement the whole widget for
	doing table editing.  Nothing done about these yet.