Created ExportOptionDialog class to be used for options (such as color format) when exporting to other formats.

Inputs:
parent is the parent of the dialog
title is a string used for the title at the top of the dialog
colorChoices is unsed, but will be used for determining which color formats can be chosen
otherChoies is a list of strings, each of which is the label to a check box option in the dialog

Attributes:
colorOption is index of the color format to be used
selections is a list of the indeces of the selected checkboxes