Generate more MachO exe boilerplate

* Convert draft to generate all relevant segments and sections in right places
* Do not prealloc space in text blocks until we can NOP
* Write out LC_LOAD_DYLINKER command
* Add LC_LOAD_DYLIB command in order to specify to load libSystem
* Redo update decl exports (similar to Elf globals, globals need to be contiguous in
  memory)
a927f24201Jakub Konka committed on 10/4/2020, 1:31:47 PMparent57a81bb
2 files changedLine totals unavailable