Reusing debug config name overwrites old config

[Per Östlund]

Steps to reproduce:

1. Create two debug configurations in OMEdit called test1 and test2.
2. Rename test1 to test2

The result is that the new test2 overwrites the old one without any warnings, and only one configuration is left. OMEdit should at least ask permission before overwriting the old configuration, or just refuse to change the name.

[Adeel Asghar]

This is not valid anymore. When I go to rename test1 to test2 I get the error,

A debug configuration with name <b>test2</b> already exists. Error occurred while saving the debug configuration <b>test1<b>.

I think it was fixed sometime ago.