Removed redundant "Properties" menu item in the Cross Section control.

Hi everyone,

This is a fix for [McV Inquiry 1400](http://dcdbs.ssec.wisc.edu/inquiry-v/?inquiry=1400). To recap:

> When you create a cross section display, there are two menu items that take you
> to the Properties of the Cross Section:
>
>1. Edit > Properties > Cross Section
>2. View > Cross Section > Properties

This commit removes that second menu item.