lib/ReaderWriter/ELF
~~~~~~~~~~~~~~~~~~~~

- Implement processing of DT_NEEDED elements including -rpath-link /
  -rpath processing.

- _GLOBAL_OFFSET_TABLE should be hidden and normally dropped from the output.

- Merge SHT_NOTE sections only if applicable.

- Do not create __got_* / __plt_* symbol table entries by default.

- Weak references to symbols defined in a DSO should remain weak.

- Fix section flags as they appear in input (update content permissions)

- Check for errors in the ELFReader when creating atoms for LinkOnce
  sections/Group sections. Add tests to account for the change when it happens.
