Proposed for 2.0.7:
	Mutex::protect/release unchanged - const readonly, no need to protect
	
	Add int fsys::seek() as overload to preserve existing abi linkage

	Add int fsys::trim() in some form

	Add derived mapped memory object??
	
Proposed ABI changes:

	Mutex::protect/release use "const" void object pointers...?

	Re-think mapped memory for smart self management?

	Use int return for fsys::seek()

	Add ftruncate and fsys::trim()

	Add "joinable" bool for handling of join when running thread terminated
    so that isRunning() has "expected" behavior?

	Remove explicit thread exit calls from exit() methods (keep in 2.0.x
	but note as depreciated, remove in 2.1?  no abi/link changes?)

	String::token and returning char * vs const char *

Other proposed changes:

	Remove pthread_exit/pthread_xxx re-defintion macros; no user code should
	ever use "pthread_xxx" methods.

	Use NSPR as an alternate thread runtime base like we do with GNU pth...
	Especially convenient with common use of nss for future tls.  Do we
	still keep GNU pth option if we do this?

	Use NSPR code base for simulating msw conditional variables for direct
	native msw threading if better than code we have in ucommon, or maybe
	use NSPR in place of native msw threading entirely?

	Add serialio class?

Rejected changes:

	DetachedThread delete this into dealloc() virtual...
		- use Thread::exit() virtual for this purpose instead


