This change implements a new approach to function call logging, that's
based on the GCC flag: -fpatchable-function-entry. Read the commentary
in build/config.mk to learn how it works.
- Fix some minor issues in ar.com
- Have execve() look for `ape` command
- Rewrite NT paths using /c/ rather /??/c:/
- Replace broken GCC symlinks with .sym files
- Rewrite $PATH environment variables on startup
- Make $(APE_NO_MODIFY_SELF) the default bootloader
- Add all build command dependencies to build/bootstrap
- Get the repository mostly building from source on non-Linux
