Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

preload-relocations.test
// RUN: llvm-objdump --macho -r %p/Inputs/macho-preload-x86_64 | FileCheck %s

CHECK: Local relocation information 1 entries
CHECK: address  pcrel length extern type    scattered symbolnum/value
CHECK: 00000000 False quad   False  UNSIGND False     2 (__TEXT,__cstring)