readmidi.c: make sure that malloc() is successful in
read_meta_data(), read_midi_event(), read_midi_file(),
and in groom_list().
instrum.c: remove the noluck variable and directly
check whether the file pointer is NULL.
* finalize the malloc() safety: instrum_dls.c still has to be
  edited, but it is not built by default, either:
* instrum.c: make sure that malloc() is successful. clear the
  allocated memory for ip and its sample in order to help the
  error handling and/or freeing routines. make sure that sample
  pointer is valid in free_instrument().
* timidity.c: make sure that malloc() is successful in
  mid_song_load_dls(). use safe_free() whenever possible in the
  song freeing processes.
minor comment and coding style tidyup.
intrum_dls.c: apply the same one extra sample space fix
to load_region_dls() to cure memory error reports from
valgrind. removed a comment from instrum.c:free_bank()
which is no longer valid. minor tidy-ups here and there.
resample.c (pre_sample): a simplification (use v5 as an
intermediate variable in computation of v) and a fix
(assignment of last two samples) from timidity++.
renamed the macro FSCALE to TIM_FSCALE to avoid possible
clashes with system headers. renamed FSCALENEG to TIM_FSCALENEG
for consistency. new macro names are in line with timidity++-2.xx.