AttentionValue simplifcation -- everythng compiles

Unit tests are crashing; we'll fix those next
Stupid bug fix in new code
port the examples over, as well.
AttentionValue further simplification
Merge pull request #351 from linas/master

Simplify how AttentionValue is used.
Added precondition satisfaction check to selecting best numeric value from candicates.
atospace misc minor cleanup
atomspace: remove some old cruft.
tomspace: remove more cruft
atomspace: remove some pointless code.
atomspace: remove more deadwood
benchmark performaance update
atomspace: bugfix in new code.

When removing an atom from a table; really remove it completely.
atomspace: remove old cruft
atomspace: remove more dead code.
atomspace: remove no-op code
Atomspace: Move signals to where they belong
async test: fix test for the new semantics

the atom is still in the table when the remove signal shows up.
This gives users a last-chance to do stuff.
atomspace: remove pointless, duplicated code
benchmark: remove oddball directive