Touches most files in bfd/, so likely will be blamed for everything..

Touches most files in bfd/, so likely will be blamed for everything..

o  bfd_read and bfd_write lose an unnecessary param and become
   bfd_bread and bfd_bwrite.

o  bfd_*alloc now all take a bfd_size_type arg, and will error if
   size_t is too small.  eg. 32 bit host, 64 bit bfd, verrry big files
   or bugs in linker scripts etc.

o  file_ptr becomes a bfd_signed_vma.  Besides matching sizes with
   various other types involved in handling sections, this should make
   it easier for bfd to support a 64 bit off_t on 32 bit hosts that
   provide it.

o  I've made the H_GET_* and H_PUT_* macros (which invoke bfd_h_{get,put}_*)
   generally available.  They now cast their args to bfd_vma and
   bfd_byte * as appropriate, which removes a swag of casts from the
   source.

o  Bug fixes to bfd_get8, aix386_core_vec, elf32_h8_relax_section, and
   aout-encap.c.

o  Zillions of formatting and -Wconversion fixes.