[TextMate] Xcode external editor support

[Chris Thomas]

I'm using TextMate as my Xcode external editor. This works pretty well,  
but I have a couple of problems:

(1) TextMate doesn't seem to support the external editor interface.  
Specifically, what seems to be missing is the ability to go directly to  
a specified line when opening a file. This is described here:

    http://www.codingmonkeys.de/techpubs/externaleditor/ 
pbxexternaleditor.html

Remarks	Metrowerks state in their documentation that the IDE (here  
Project Builder) uses the optional keyAEPosition parameter to tell the  
editor the selection range. If lineNum is zero or greater, scroll the  
text to the specified line. If lineNum is less than zero, use the  
values in startRange and endRange to select the specified characters.  
Scroll the text to display the selection. If lineNum, startRange and  
endRange are all negative, there is no selection range specified.

Basically, intercept the odoc AppleEvent and read the optional  
parameter for line number or selection information.

(2) When I open a TextMate document that I already have open, TextMate  
creates a new window for it and leaves the old window open too. This  
can be very useful under special circumstances, however -- more  
frequently -- it just rapidly and pointlessly clutters up my desktop.  
Creating a new window is useful, but should be an optional behavior.  
Usually, what I'm trying to do when I open a document is navigate to an  
existing window, relying on the standard Mac UI behavior. I will  
frequently double-click a file in the Xcode project window to get back  
to TextMate, most often a file I already have open.

Chris