Changes how mensural flags are drawn

Issue 3105 complains that mensural flags do not attach to stems very well.  This patch makes them attach in the same way as modern flags, and changes how they're drawn - I think the way this is now done is more metafont-y.  It also gets them looking closer to all the 16C flags I can find.

[PhilEHolmes, 2013-08-20 13:15:33]

Please review.

[janek, 2013-08-20 15:24:16]

code LGTM, and i like the new shapes.

[lemzwerg, 2013-08-20 16:40:59]

LGTM, except indentation: In MF files, we use real tabs.

[mail_philholmes.net, 2013-08-20 17:03:12]

----- Original Message ----- 
From: <lemzwerg@googlemail.com>
To: <PhilEHolmes@googlemail.com>; <janek.lilypond@gmail.com>
Cc: <reply@codereview-hr.appspotmail.com>; <lilypond-devel@gnu.org>
Sent: Tuesday, August 20, 2013 5:40 PM
Subject: Re: Changes how mensural flags are drawn (issue 13122044)


> LGTM, except indentation: In MF files, we use real tabs.
>
> https://codereview.appspot.com/13122044/


Aaargh.  Thought I'd got that right, but it looks like I missed the 'save 
flag_end, flag_right' line?  Think the rest are all OK?

--
Phil Holmes 

[lemzwerg, 2013-08-20 17:10:33]

Well, in other MF source files the `fill' operator's arguments are aligned
vertically also:

  fill z1
       .. z2
       .. z3

The alignment consists of zero or more tabs plus the necessary spaces.

[mail_philholmes.net, 2013-08-20 17:19:51]

----- Original Message ----- 
From: <lemzwerg@googlemail.com>
To: <PhilEHolmes@googlemail.com>; <janek.lilypond@gmail.com>; 
<mail@philholmes.net>
Cc: <lilypond-devel@gnu.org>; <reply@codereview-hr.appspotmail.com>
Sent: Tuesday, August 20, 2013 6:10 PM
Subject: Re: Changes how mensural flags are drawn (issue 13122044)


> Well, in other MF source files the `fill' operator's arguments are
> aligned vertically also:
>
>   fill z1
>        .. z2
>        .. z3
>
> The alignment consists of zero or more tabs plus the necessary spaces.
>
> https://codereview.appspot.com/13122044/


Please remind me how many spaces are in a standard lilypond MF tab?

--
Phil Holmes 

[PhilEHolmes, 2013-08-22 14:07:32]

Formats tabs as per Werner's request

[PhilEHolmes, 2013-08-22 14:09:07]

Please review.

[lemzwerg, 2013-08-23 05:20:14]

LGTM, thanks.  In case you have time, you might replace

  { foo } z1 { bar }

with

  {foo}z1{bar}

for consistency with other files, but this is not really important.