MachO files duplicate symbols

[staticfloat]

MachO files create duplicate symbol entries, one local and one global. Figure out how to synthesize these properly.

[staticfloat]

Example:

julia> oh = readmeta("mac64/libfoo.dylib")                                                                         [6/8010]
MachO Handle (64-bit)

julia> syms = Symbols(oh)
MachO Symbol Table
  MachOSymbol (64 bit) "/Users/sabae/.julia/v0.6/BinaryBuilder/test/build_tests/libfoo/"
  MachOSymbol (64 bit) "libfoo.c"
  MachOSymbol (64 bit) "/tmp/cci1ObrT.o"
  MachOSymbol (64 bit) ""
  MachOSymbol (64 bit) "_foo"
  MachOSymbol (64 bit) ""
  MachOSymbol (64 bit) ""
  MachOSymbol (64 bit) ""
  MachOSymbol (64 bit) "_foo"
  MachOSymbol (64 bit) "dyld_stub_binder"