* manual/signal.texi: Document MTASC-safety properties.
* manual/socket.texi: Document MTASC-safety properties.
* manual/startup.texi: Document MTASC-safety properties.
* manual/sysinfo.texi: Document MTASC-safety properties.
* manual/syslog.texi: Document MTASC-safety properties.
* manual/stdio.texi: Document MTASC-safety properties.
* manual/threads.texi: Document MTASC-safety properties.
* manual/string.texi: Document MTASC-safety properties.
* manual/time.texi: Document MTASC-safety properties.
* manual/string.texi (wcstok): Fix prototype.
(wcstok, strtok, strtok_r): Adjust reentrancy remarks.
* manual/intro.texi: Document safety identifiers and
conditionals.
* manual/errno.texi: Document MTASC-safety properties.
* manual/filesys.texi: Document MTASC-safety properties.
* manual/terminal.texi: Document MTASC-safety properties.