Boot Levels

Updated 29-Sep-2010: no longer using integers

PROPOSED: Subject to Change

This feature is intended for advanced programmers developing new resident mezzanines or modules.

A new --boot command line option controls the boot level:

	base	initialize only the lower levels. This option is for special purpose testing only because it provides no way to load external code. (No schemes, such as file access, nor `load` or `do` functions.) If your host-kit build is crashing on startup, you can use this option to confirm that the exe image is loadable and runable.
	sys	initialize up to and including the basic runtime lib and sys contexts. This option allows you to run a very "lean" system (minimal memory and boot time) where your code will be supplying all other run-time functions and modules. Provides a basic `load` function but with very limited special options (no `import`, needs, versions, or related features.)
	mods	initialize up to and including lower-level resident modules. In addition to boot-sys, this level adds high-priority resident modules, but not mezz plus (higher level mezzanines).

For example,

r3 --boot base mycode.r

When no option is specified, all resident features are enabled, including mezz plus and all other resident modules.