[emacs] Never remove windows' horizontal split

Usually, my Emacs frame is wide enough to have two 80-column wide
windows.  Problem is that with such a set-up, and default key
bindings, “C-x 1” leaves only one window in a frame removing the
horizontal split.

Changing “C-x 1” to only affect vertical split makes it easy to
join all windows in given column without affecting the other
column, which is exactly what I want.
[emacs] Close read-only buffers with “q”

I often hit “q” in read-only buffers (such as source Elisp files)
treating them a bit like help buffers (and other such buffers), but
that results in Emacs screaming at me.  To fix that, this commit
changes binding of “q” so that it kills current buffer if it's
read-only, and inserts “q” otherwise.
[emacs] Open web pages in Opera
[emacs] Make F4 apply macro to region if active
[emacs] Do not match new line with space in interactive search
[emacs] Drop C-F5 for manually syncing mail

Because C-F5 made it so easy to sync mail, I kept doing it all the
time manually, circumventing automatic syncing which happens every
hour.  This in turn, decreased my productivity since I spent to much
time on reading and managing mail instead of doing that in batch.
[shell] Remove dedal specific configuration

I don't even have access to dedal any more.  No need to keep
configuration for that machine any more.
[shell] Enable autocd in Bash
[shell] Fix powerful cd, namely the substitution functionality
[shell] Further cd related aliases
[git] Remove “+” binary and replace it with aliases

Also add “+u” and “+p”.