Enhancement: more logical ambitus placement

[Simon Albrecht]

Hello,

currently, ambitus are placed at the very beginning of the first system, 
before clef and key signature. However, its meaning depends on both: 
without a clef, the pitches are unspecified, and it’s confusing that 
accidentals are set based on a key which has not yet been ‘announced’ 
(See also <https://code.google.com/p/lilypond/issues/detail?id=762>; 
there used to be a workaround with \set Staff.keySignature = #'() which 
doesn’t work anymore).
I suggest to place the ambitus between key and time signatures, as seen 
in the attachment.
The values in the space-alists are more or less wild guesses, as I don’t 
have much experience with this kind of settings.
Do we really need an entry for ambitus in break-align-orders except for 
beginning of line?

Yours, Simon

ambitus-place-comparison.ly
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ambitus-place-comparison.png
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