#13 Added Import CSV Feature

[Tetra]

The Insert Table/Matrix dialogue now gives the option of importing data from a CSV file. Scientific notation (e.g., 3.12E-12) is automatically converted to LaTeX code.

This is my first exposure to the dev side of a lot of the technology involved (pyGTK, glade, gedit plugins, svn, and sourceforge), so if there are any stupid mistakes, I would appreciate your patience and your feedback.

[Tetra]