Reworked PS1 handling.

This makes it easier to add more status prompt commands adding
more data to the prompt line.
[update] Use # as sed's regex separator.

Previously used dash turnes out to be not that uncommon to be
present in user names.  Hash should be less common.
[update] Use mktemp rather than tempfile.

Default installation of Amazon Linux lacks tempfile command but
mktemp is there, so just use it.
[shell] Protect against lack of Emacs.
Revert "[bash] Drop ~/.bash_local support."

There are some instances where .bash_local is actually useful
so get it back.

This reverts commit aa52739bd67f13983f97846ec8b3e5b5ff62eb65.
[a] Add yum support.
[shell] Disable auto-completion.
[shell] Do not change TERM from rxvt to xterm any more.

This caused weird problems where I was unable to type next command
while one was running (stdin was sort of flushed on each command
prompt) and I have no idea what issues the comment is talking
about. ;)
[emacs] Refactor mn-other-window.
[emacs] Change rules for deciding email identity.

If there is at least non-Google address in To, CC or BCC headers,
use my private email address.
[emacs] Remove custom argument lining up function.
[emacs] Use setq.
[emacs] Wrap line longer than 80-character.
[git] Add git email alias.
[xinitrc] Remove redundant redirect.
[xinitrc] Log output of the background process with the rest.
[xinitrc] Do more stuff in the background.
[xinitrc] Set keymap with setxkbmap.

Like comment says, xdotool has issues if that's not done.
[xinitrc] Remove unused code.