Redesign of "Configure Launches" dialog

[Sven Brauch]

Hi there!

I think most people here agree that the current "Configure launches"
dialog is quite horrible. Let me quickly summarize the main pitfalls:
1. Undiscoverable: I guess most users won't find out that you can
switch the launch configuration type to "Script" in the tree view. You
have to horizontally scroll that treeview to uncover an unseen colum,
then double-click some text which doesn't look like you can click it
to activate a drop-down-list. This is especially relevant for me, as
the python plugin requires this functionality to be easy-to-find.
2. Unpractical: Even if you know how it works, the whole thing feels
really sluggish to do, because of the tiny hard-to-find "add" buttons
and the vertical scrolling.
3. Illogical: Why is "Debug" a sub-item in the treeview for the launch
configuration? In my eyes, that doesn't make any sense. The whole
tree-view seems overkill for a top-layer which often has only one item
(at least I seldom have more than one or two projects opened), which
often only has one or two sub-items (the configurations) which also
have exactly one sub-item.

Anyway, enough said about the old one. Here's my suggestion for a new
dialog, which I'd like to discuss and improve:
    http://imgur.com/a/lnciJ#0
Here's the UI file:
    http://files.feorar.org/launchdialog2.ui

Changing the "Program type" dropdown thing to something else would
change the tab layout (for example add an "interpreter" tab).
Please tell me what you think. Of course it's totally non-functional,
currently (the UI file is just a mockup).

Greetings,
Sven