Docs: Issue 4181: Expose \stemUp and \stemDown predefs less

Docs: Issue 4181: Expose \stemUp and \stemDown predefs less

in LM Tweaking output
  - change some examples to use \slurUp etc rather than \stemUp
  - give an example showing the use of the direction indicators
  - replace mention of \stemUp in text with \tieUp, etc
  - correct a few typos

in NR Changing defaults
  - remove superfluous \stemUp

[Trevor Daniels, 2015-03-06 23:45:26]

This patch eliminates virtually all mention of the
\stemUp and \stemDown predefs from the LM.  Most of
the uses of these predefs in the NR are sensible, so
I have left untouched the ones in ancient, editorial,
percussion and staff.  Apart from the bald mention in
staff, these are all in rather esoteric sections and
probably quite well-hidden from new users.

Trevor

[Trevor Daniels, 2015-03-12 18:39:17]

Pushed to staging as
f5fe565be2b3662bc5fedb1f40a337c3ad0d08f4

Author: Trevor Daniels <t.daniels@treda.co.uk>  2015-03-06 23:29:19
Committer: Trevor Daniels <t.daniels@treda.co.uk>  2015-03-12 18:34:49

    Docs: Issue 4181: Expose \stemUp and \stemDown predefs less
    
    in LM Tweaking output
      - change some examples to use \slurUp etc rather than \stemUp
      - give an example showing the use of the direction indicators
      - replace mention of \stemUp in text with \tieUp, etc
      - correct a few typos
    
    in NR Changing defaults
      - remove superfluous \stemUp

Closing ...