Canceling and clearing things
---------------------------------------------------------
cancelCenteringHidingPreContacts() turns off those processes
  without changing the current scene (except to hide the target asterisk
	marks from preContacts).

clearControls() calls above and also ends use of the contacts controls.

CONTACTS

selectMode "" or "c" (chain) etc.
  is the main indicator of whether preContacts is in progress.
	When not "", clicking on something toggles its target status and
	re-displays the pre-contacts help.
	When "", clicking shows the identity and HIDES target marks! 

contactsShowing t/f controls ablity to return to contacts controls after
	contacts have been shown.

markContactsTargets t/f controls display of * on targets.
  but in makeMarkContactsTargetSpt(), contactsShowing must also be true
	or selectMode != "" is sufficient to mark the targets.

resetContacts() (jcontrol.js) resets all contacts display control
	options prior to a new cycle.

clearSelectedArrays() prepares for contact target selection.
  It is called in doViewLink() before preContacts so should be unnec. to
	call it elsewhere (tho it has been).

HIDING

clearSpt hides everything.

clearHidden unhides anything hidden.

hideMode t/f controls whether clicking something hides it.

cancelHiding() shows help 
cancelHidingNoHelp() does not show help (jcontrol.js)

CENTERING

cancelCentering() (jcontrol.js) shows cancel centering help.

cancelCenteringNoHelp()