Initial reduction of make doc op - Issue 2075

Initial reduction of make doc op - Issue 2075

This proposed patch reduces output to 113,500 lines by pushing lilypond output to logfiles.  If there is an error with lilypond-book trying to compile a lilypond file, it issues a simple error message pointing at the relevant logfile and exits.

[PhilEHolmes, 2011-12-05 14:41:09]

Please review simple initial patch.

[Graham Percival, 2011-12-07 08:03:45]

Great start!  There's a problem but I think I found out why.

1) (not the problem)  could you print a blank line before+after the "Please see"
block?  That would help it to "stand out" more.

2) (problem)  I added a mistake to something in tutorial.itely, and then got
this:

Child returned 1
Error ignored by lilylib
Error trapped by lilypond-book
Please see
/main/src/lilypond/build/out/lybook-db/snippet-names--8702389846796748212.log
make[2]: *** [out-www/learning.texi] Error 1
make[2]: Leaving directory `/main/src/lilypond/build/Documentation'
make[1]: *** [WWW-1] Error 2
make[1]: Leaving directory `/main/src/lilypond/build'
make: *** [doc-stage-1] Error 2

gperciva@chikara:~/src/lilypond/build$ more
/main/src/lilypond/build/out/lybook-db/snippet-names--8702389846796748212.log
/main/src/lilypond/build/out/lybook-db/snippet-names--8702389846796748212.log:
No such file or directory

http://codereview.appspot.com/5453046/diff/1/python/lilylib.py
File python/lilylib.py (right):

http://codereview.appspot.com/5453046/diff/1/python/lilylib.py#newcode196
python/lilylib.py:196: stderr_filename = ' '.join([log_file, '.log'])
I think this should be:
   stderr_filename = ''.join([log_file, '.log'])
or just
   stderr_filename = llog_file + '.log'

I mean, we don't want a space in the filename, right?

[Graham Percival, 2011-12-10 04:52:22]

LGTM, fantastic work.  This alone will save people *hours* of frustration.