Improve Breakpoints Window

[Johannes_T]

Summary:

Improve the Breakpoints Window, so that breakpoints can be more easily managed.

Description:

1. Change the Breakpoints Window, from a modal dialog to a dockable window (similar to the Watch Window). Debugging can be more easy this way.

2. Allow breakpoints to be grouped, disabled/enabled and edited in user defined categories. This allows users to easily collectively manage several breakpoints at a time. It also helps the user to logically group breakpoints, depending on various issues issues that he might be working on.

3. Breakpoints could also be sorted from a pop-up menu by filename, line, hit count, etc.