#21 Change directory to current documents

[Jon Pheasant]

It would be nice to be able to change the current directory which
appears in the open dialogue and the file explorer pane by either
right clicking or using a shortcut from the current document being
edited. The "Change To File Directory" is in Programmers File
Editor (PFE) and is a very useful feature, especially when the file
explorer pane doesn't show the desktop.