TODO
[scripts, wrapper] Uninstall DESTDIR files from global install directory

This script, given a component name, a DESTDIR, and a global install
directory, will remove the corresponding DESTDIR files from the global
install directory.

This effectively 'uninstalls' the current component.

Also provides a global definition of the script for use by the
wrapper.
[wrapper] Delete files from global install directory on 'clean'

This change updates the generated 'clean' rule to also remove the
contents of the current DESTDIR from the global install directory.
[scripts] Fix Manifest Checking

A recent discovery shows that mtree does not return a non-zero error
code (indicating a mismatch between the current directory and the
stored manifest when files are deleted from the directory.

Instead, mtree prints, to stdout, that files have been deleted and
returns 0 if no other mismatches occur.

This change fixes this deficiency of mtree by checking for deleted
files and properly reporting that the component has changed.

This is a stand-alone precursor for detecting when files have been
deleted from the component's source directory and automatically
deleting the build & destdir directories before syncing the source.
[wrapper] Move sentinel files in preparation for deleted file fix

Sentinel files stored directly in the build directory will be deleted
when the build & destdir directores need to be deleted before syncing
a component's sources to the build directory.

The component's build & destdir directories need to be deleted before
syncing the component sources when files have been deleted from the
component source directory.

Failure to delete the files can yield bad builds.

This change moves the sentinel files so they will not be affected by a
follow-on change to deal with files deleted from the component source
directory.