Bug Fixes
* revisit the lazy dynamic-wind code
* make implementations of srfis 12 and 34 fully compliant with spec
* make let-syntax strictly r5rs compliant when strict compliance is
  demanded
* Work to eliminate bottlenecks in generic-procedure calls.

General
* Document weak hashtables
* do a code walk to weed out anything that breaks thread-safety
* produce a validation testing framework that is invokable from ant
* produce a performance testing framework that is invokable from ant

Features
* Support for composable IO.
* rationalize/integrate modules, libraries, slib
* implement random-access files
* write a debugger
* port scsh's SREs
* mechanism to construct immutable objects other than literals
* direct implementation of shift and reset
   http://citeseer.nj.nec.com/gasbichler02final.html
  but make sure it plays nicely with dynamic-wind
