First stab at scribble docs. Introduction and Process Notation chapters.
Quiet scribble warnings with #:link-target?.

I don't use defform/none because it changes the style used for the form's name.
Note to self in introduction. Whitespace fix in process-notation.
First partial cut of the system calls chapter. Changes to newports related.

Make seek and tell require file descriptor arguments, since buffering can't
be changed on ports anymore.
Indentation fixes. Clear up some missed tex-isms.
Add docs for open-file, open-input-file, and open-output-file.

Associated code changes, mostly for clarity.
Remove open-fdes; s48 makes it not so simple to implement with file-options.
Reformat collect-char! and string-collector->string so I can see wtf is happneing.
Remove scsh-read/write.

It's an abomination; equates strings to byte buffers.
Add doc for pipe.
Fix contract for make-string-port-filter in docs.
Remove buffered-io-flags package.
Fix tests that depended on write-string.
Add (much abridged) Buffered I/O section to docs.
Remove scsh-flock-interface. Unused for a while now.
Code changes to use s48 file-modes more consistently across scsh.
Beginning of Filesystem section in syscalls documentation.
More Filesystem docs.
Add docs for set-file-times, sync-file*, and truncate-file.
Document file-info and friends. Introduce file:*.