Release notes for version 1.8

An experimental framework for asynchronous events from external code was added. It's now used for asynchronous host-name lookups on systems with pthreads.
Support for 64-bit architectures was added (thanks to Taylor Campbell, Marcus Crestani, and David Frese)
The installation now includes an (experimental) scheme48-config script that reports C compiler and linker and associated flags that may be used for compiling dynamic externals.
The layout of the installed system now conforms to FHS.
The old dynamic-loading code was removed; correspondingly, the -o flag for scheme48vm was removed.
The filename translations apply to dynamic externals as well.
On Unix, the central event loop uses poll() instead of select() on systems that have it (thanks to Marcus Crestani)
The external code for the POSIX libraries and SRFI 27 was moved to dynamically-loaded externals. (Cygwin support for this thanks to Harald Glab-Plhak)
Bug fixes:
A bug in the division simplifier of the PreScheme compiler was fixed.
The PreScheme compiler can now emit code for unsigned longs.
The implementations of SRFI 19 and SRFI 42 now include the latest fixes from the reference implementations.
A race condition in the implementation of queues was fixed.