Fixes various warnings from clang++

Fixes various warnings from clang++

These changes leave the regtests unchanged.
This is a branch with a series of commits; 1 commit per file.


Avoid redefining struct String_convert to class.


Avoid comparison of unsigned < 0

  PyArg_ParseTuple (args, "s#|i", &track, &track_size, ...
returns the length as an int:
  http://docs.python.org/c-api/arg.html#PyArg_ParseTuple

Avoid implicit sign conversion


Remove default comparison for binary search

clang++ complains about this, and we never rely on the default
comparison in our code.

/home/gperciva/src/lilypond/flower/include/std-vector.hh:197:36:
error: 'T' does
      not refer to a value
               Compare less = less<T> (),
                                   ^
/home/gperciva/src/lilypond/flower/include/std-vector.hh:193:19:
note: declared
      here
template<typename T, typename Compare>
                  ^
/home/gperciva/src/lilypond/flower/include/std-vector.hh:197:40:
error:
      expected expression
               Compare less = less<T> (),

Avoid conversion changing signedness

/home/gperciva/src/lilypond/flower/file-cookie.cc:45:50: error: implicit
      conversion changes signedness: 'int' to 'size_t' (aka 'unsigned long')
      [-Werror,-Wsign-conversion]
    return Memory_out_stream::writer (file, buf, i);
           ~~~~~~~~~~~~~~~~~                     ^

[Graham Percival, 2011-12-09 14:21:09]

A few minor fixes; I think they're all ok, but I can't claim any deep
understanding of the code in question.

Regtests were unchanged.