[tweak] Allow tweaks to masquerade as bundles if and only if xxx_BUNDLE_RESOURCE_??? is present, defaulting to /Library/Application Support/xxx/xxx.bundle (configurable with xxx_BUNDLE_INSTALL_PATH, xxx_BUNDLE_NAME and xxx_BUNDLE_EXTENSION.)
!WIP [nic] Allow the user to override the name the Makefile uses to refer to Theos.
!WIP [makefiles] Try to intuit the Makefile the user is using (make -f XXX), and use that for all sub-makes.
!WIP [rules] Rewrite the linking rules to use "stages", a complex system that allows link steps to be swapped out, reordered and removed without having to fix all their dependencies.
!WIP [makefiles/tweak] Don't kill SpringBoard, kill whatever the user says to kill when building the template.