CogVM binaries as per VMMaker.oscog-eem.842/r3058

Spur:

Provide unpinObject: for InterpreterProxy.

Fix initialization of the heap-resident remembered set added by

VMMaker.oscog-eem.827. ��It must be created /after/ old space is initialized.

Fix two become bugs surfaced when adding/removing inst vars to/from Association,

Binding et al. ��First, the class table must be scanned to ensure there are no

forwarders to classes (much cheaper than the full hierarchy walk to follow

method dictionaries etc that was done). ��Second, machine code methods that gain

a new reference through become must get added to the youngReferrers. ��Add a new

become effect flag, OldBecameNew that captures this and respond to it in

CoInterpreter>>postBecomeAction: by adding all methods to youngReferrers so

that on the next scavenge all will be made right.

Fix GC of machine code, which must follow forwarders when doing

markAndTraceLiteral: and again add to youngReferrers if following

gains a new ref. ��Refactoring of markAndTraceLiteral: into

markAndTraceLiteral:in:at: et al required.

Fix assert in addFreeSubTree:.

General:

Support the alternate bytecode set header in all VMs to ease testing of

multiple bytecode sets. ��This means methods with the sign bit set have

no primitive field and a larger num literals field, but no more.

Fix longPrintOop: (actually printOopShortInner:) for

global variable printing in face of new Environments.

Cogit:

Clean up adding to the youngReferrers by providing ensureInYoungReferrers:.

Since there always is room on youngReferrers, nuke roomOnYoungReferrersList,

canLinkToYoungClasses and caller code, simplifying ceSend:super:to:numArgs: etc.

Fix assert in followForwardedLiteralsIn:

General:

Change the scanning for initial nils scheme in the StackToRegisterMappingCogit

to answer the number of push nils in a bytecode, instead of whether the

bytecode is a push nil. ��Refactor genReturnTopFromBlock into genBlockReturn.

These changes accomodate Sista.

Rationalize the length functions, deleting byteLengthOf:, fetchLong32LengthOf:

& fetchWordLengthOf: and providing numBytesOf:, num16BitUnitsOf:,

num32BitUnitsOf:, num64BitUnitsOf: and numBytesOf:.

Provide fetch/storeShort16:ofObject:[withValue:] and

fetch/storeLong64:ofObject:[withValue:].