When dumping clear the arm/thumb flag for now.

Patch by Nico Rieck!
Implement sectionContainsSymbol for ELF.

Patch by Nico Rieck!
Don't disassemble symbols with an unknown address or size.

Patch by Nico Rieck!
Implements low-level object file format specific output for COFF and
ELF with support for:

- File headers
- Section headers + data
- Relocations
- Symbols
- Unwind data (only COFF/Win64)

The output format follows a few rules:
- Values are almost always output one per line (as elf-dump/coff-dump already do). - Many values are translated to something readable (like enum names), with the raw value in parentheses.
- Hex numbers are output in uppercase, prefixed with "0x".
- Flags are sorted alphabetically.
- Lists and groups are always delimited.

Example output:
---------- snip ----------
Sections [
  Section {
    Index: 1
    Name: .text (5)
    Type: SHT_PROGBITS (0x1)
    Flags [ (0x6)
      SHF_ALLOC (0x2)
      SHF_EXECINSTR (0x4)
    ]
    Address: 0x0
    Offset: 0x40
    Size: 33
    Link: 0
    Info: 0
    AddressAlignment: 16
    EntrySize: 0
    Relocations [
      0x6 R_386_32 .rodata.str1.1 0x0
      0xB R_386_PC32 puts 0x0
      0x12 R_386_32 .rodata.str1.1 0x0
      0x17 R_386_PC32 puts 0x0
    ]
    SectionData (
      0000: 83EC04C7 04240000 0000E8FC FFFFFFC7  |.....$..........|
      0010: 04240600 0000E8FC FFFFFF31 C083C404  |.$.........1....|
      0020: C3                                   |.|
    )
  }
]
---------- snip ----------

Relocations and symbols can be output standalone or together with the section header as displayed in the example.
This feature set supports all tests in test/MC/COFF and test/MC/ELF (and I suspect all additional tests using elf-dump), making elf-dump and coff-dump deprecated.

Patch by Nico Rieck!