assocs: change enum to immutable-sequence.
rot13: adding some tests.
robots.txt: Bing bot spams gitweb...disable it hopefully.
Revert "robots.txt: Bing bot spams gitweb...disable it hopefully."
Found another way.

This reverts commit 7500504bc055573bc50ae5b9349a3a92a4bc237d.
unix.linux.proc: Refactor /proc parsing. Add generic to make pid/string and pid-string/string pairs into /proc/pid/pathname.
tools.ps: Use unix.linux.proc for parsing.
calendar.format: Add some utility words for implementing top.
unix.linux.proc: Add some more /proc parsing.