This reverts commit d47295f5.

This reverts commit 3964dea2.

This reverts commit 0fdcd2a4.

Conflicts:
	abstractions/Makefile

This reverts commit 86dae341.

make [declare -lib] handle absolute paths (and namespace-prefixed paths) consistent with object boxes

* the original namespace-collision checker only worked for abstractions
* trying a new namespace-collision checker revealed about 80 new clashes.
  Since there are so many it's probably too disruptive to remove them.
* probably need to revert the namespace clash abstraction removals