#123 Add-files-on-submit dialog should be resizable

[Johan Walles]

With Eclipse 3.0 & p4eclipse 0.6.24:

1. Change a file or two.
2. Do "submit".
3. A dialog with a list of files not controlled by P4
appears. I'm expected to select which ones I want to
add to version control before submitting.
4. Try to resize the dialog.

Current behaviour:
It won't resize.

Expected behaviour:
The dialog should be resizable.

Notes:
This is on Linux/GTK+.