ileo: call outerUpdate to update leo outline in pre_prompt_hook

ileo: _p does not get erased with recursive ipush / wb.require()

ileo: wb.require() for handling inter-node dependencies

use cd --foo instead of cd -foo. also cd --<TAB> works. changes.txt

cd -foo jumps to dir matching 'foo' in directory history

ILeo: LeoNode.__delitem__ and append(). Now clear() etc work

LeoNode.last_edited

ILeo: comment out format_for_leo for list (bad idea!)

Rename two tests that had identical names to distinguish them. One of these (testExecuteFailuresEngineService_0) fails often, though not always. I spent hours trying to debug what's going on but failed, and it's non-deterministic.

Reactivate completion test now that namespaces are working