zsh: Divide zshrc into zshrc.d

Move every file from plugins into zshrc.d as well as all bigger blobs in
the zshrc into their own files there.
Some stuff is still in there that I am not all too sure where it
belongs. TODO: Move.

Because all external plugins are now sourced over a symlink I had to
create a fork of fzf-tab for now that supports that.
See: https://github.com/Aloxaf/fzf-tab/pull/153

.config/zsh/zshrc.d/20-completion.zsh

@@ -0,0 +1,32 @@
+[[ ! -d "$ZSH_CONF/completion" ]] || fpath=("$ZSH_CONF/completion" $fpath)
+
+autoload -Uz compinit
+compinit -d "${XDG_CACHE_HOME:-$HOME/.cache}/zsh/zcompdump-$ZSH_VERSION"
+
+zstyle ':completion:*' auto-description 'specify: %d'
+zstyle ':completion:*' completer _expand _complete _correct _approximate
+zstyle ':completion:*' format 'Completing %d'
+zstyle ':completion:*' group-name ''
+zstyle ':completion:*' menu select=2
+zstyle ':completion:*:default' list-colors ${(s.:.)LS_COLORS}
+zstyle ':completion:*' list-colors ''
+zstyle ':completion:*' list-prompt %SAt %p: Hit TAB for more, or the character to insert%s
+zstyle ':completion:*' matcher-list '' 'm:{a-z}={A-Z}' 'm:{a-zA-Z}={A-Za-z}' 'r:|[._-]=* r:|=* l:|=*'
+zstyle ':completion:*' menu select=long
+zstyle ':completion:*' select-prompt %SScrolling active: current selection at %p%s
+zstyle ':completion:*' use-compctl false
+zstyle ':completion:*' verbose true
+
+zstyle ':completion:*:*:kill:*:processes' list-colors '=(#b) #([0-9]#)*=0=01;31'
+zstyle ':completion:*:kill:*' command 'ps -u $USER -o pid,%cpu,tty,cputime,cmd'
+
+zstyle ':completion:*' menu select
+
+zstyle -e ':completion:*:users' users 'local user; getent passwd | while IFS=: read -rA user; do (( user[3] >= 1000 || user[3] == 0 )) && reply+=($user[1]); done'
+
+# Include hidden files in completion.
+_comp_options+=(globdots)
+
+# Don't complete the same argument twice for these programs.
+# Taken from http://leahneukirchen.org/dotfiles/.zshrc
+zstyle ':completion:*:(diff|meld|trash):*' ignore-line yes