chain/persistencealg/gnp
persistence remove destroyers initial attempt.
Revert "persistence remove destroyers initial attempt."

This reverts commit b45d78f362afd4c3be743982fa69e6200d44310e.
towards supporting efficient cubical complexes.
towards generically supporting more than one cell type.
chain_complex refactor complete, templated storage is now possible.
cube musings.
cmakelists
CMake and find_package is still not *quite* good enough..
meta magic bug fixed.
updated product cell.
towards a generic Chain_complex

Conflicts:
	ctl/distributed/relative_simplex_boundary/relative_simplex_boundary.h
handrolled a multirray.
more cubical complex progress. starting cube boundary.
added cube boundary operator, tested, works. finished off cube structure as a result.
all objects implemented. simply debugging.
still debugging.
settled on a way to resolve issue with iterator inteface. lost a lot of time.
cube progress moving slowly, but, moving.
still making cube boundary wrapper progress.