Remove 404 entries

These entries are all 404, removing

https://github.com/silversteinsoftware/silverstein_quotes
https://github.com/mattmc3/zsh-xdg-basedir
https://github.com/gnsfujiwara/gnsprompt
https://github.com/mubinben/purr-zsh-theme

Signed-off-by: Joe Block <[email protected]>

Author: unixorn

README.md

@@ -1141,7 +1141,6 @@ Here are a few good sources for Nerd Fonts and Powerline-compatible fonts:
 - [shellfirm](https://github.com/kaplanelad/shellfirm) - Shellfirm is a handy utility to help avoid running dangerous commands without an extra step of approval. When risky patterns is detected you will immediately get a small prompt challenge that will verify your action.
 - [shift-select](https://github.com/jirutka/zsh-shift-select) - Emacs shift-select mode for ZSH - select text in the command line using Shift, as in many text editors, browsers and other GUI programs.
 - [show-path](https://github.com/redxtech/zsh-show-path) - Provides a function shows the `$PATH` line by line.
-- [silverstein-quotes](https://github.com/silversteinsoftware/silverstein_quotes) - Show a random quote from a Silverstein song during shell startup.
 - [simpleserver](https://github.com/sathish09/zsh_plugins/tree/master/simpleserver) - Plugin to easily start python `SimpleHTTPServer` and `SimpleHTTPSServer`.
 - [singularityenv](https://github.com/saravanabalagi/zsh-plugin-singularityenv) - Provides a `singularityenv_prompt_info` function which returns the current singularity environment name
 - [skaffold](https://github.com/todie/skaffold.plugin.zsh) - ZSH integration and completions for [skaffold](https://skaffold.dev) local kubernetes development environment.
@@ -1280,7 +1279,6 @@ Here are a few good sources for Nerd Fonts and Powerline-compatible fonts:
 - [workon](https://github.com/bryanculver/workon.plugin.zsh) - Simple utility for jumping between projects.
 - [worktree](https://github.com/jspears/worktree) - Adds functions that wrap `git worktree`.
 - [wsl2-ssh-pageant](https://github.com/antoinemartin/wsl2-ssh-pageant-oh-my-zsh-plugin) - Use your Yubikey stored GPG keys from WSL. This packages the instructions from [wsl2-ssh-pageant repo](https://github.com/BlackReloaded/wsl2-ssh-pageant) as a ZSH plugin.
-- [xdg-basedir](https://github.com/mattmc3/zsh-xdg-basedir) - Supports [XDG](https://wiki.archlinux.org/index.php/XDG_Base_Directory) base directory settings.
 - [xxh-plugin-zsh-zshrc](https://github.com/roman-geraskin/xxh-plugin-zsh-zshrc) - plugin for [xxh-shell-zsh](https://github.com/xxh/xxh-shell-zsh) that copies your `~/.zshrc` to a remote host and sources it with [xxh-shell-zsh](https://github.com/xxh/xxh-shell-zsh).
 - [yadm](https://github.com/juanrgon/yadm-zsh) - Displays a warning if there are local [yadm](https://thelocehiliosan.github.io/yadm/) configuration changes.
 - [yapipenv](https://github.com/AnonGuy/yapipenv.zsh) - Automatically activate a directory's `pip` environment if `pipenv` detects the presence of one.
@@ -1821,7 +1819,6 @@ If you're using [Antigen](https://github.com/zsh-users/antigen), you can test th
 - [glimmer](https://github.com/martnu/glimmer) - Includes `git` branch, time and user@host decorators.
 - [gndx](https://github.com/gndx/gndx-zsh-theme) - Includes `git` status, hostname, directory and last command exit status decorations.
 - [gnrnzh](https://github.com/PaoloneM/gnrnzh-zsh-theme) - Customization of [gnzh.zsh-theme](https://github.com/ohmyzsh/ohmyzsh/blob/master/themes/gnzh.zsh-theme) from oh-my-zsh.
-- [gnsprompt](https://github.com/gnsfujiwara/gnsprompt) - Minimal prompt with decorators for root status and current directory.
 - [gocilla](https://github.com/goranvasic/gocilla-iterm-zsh) - Theme for iTerm 2 and ZSH. Uncludes `git` status, user@host, path and date decorators.
 - [goprompt](https://github.com/NonLogicalDev/shell.async-goprompt) - Lightning fast. Includes decorators for truncated current directory, last command duration & exit status, vim-mode indicators, `git` information, datetime and parent process name.
 - [gops](https://github.com/noxer/gops) - Fast powerline-like prompt. Includes `git` status, current directory, root status decorations.
@@ -2159,7 +2156,6 @@ If you're using [Antigen](https://github.com/zsh-users/antigen), you can test th
 - [purify (kyoz)](https://github.com/kyoz/purify) - A clean and vibrant theme, best on dark backgrounds. Includes `git` status decorations.
 - [purity](https://github.com/petermbenjamin/purity) - Inspired by the [robbyrussell](https://github.com/ohmyzsh/ohmyzsh/blob/master/themes/robbyrussell.zsh-theme) theme and the [pure](https://github.com/sindresorhus/pure) prompt.
 - [purpleblood](https://github.com/HFMorais/oh-my-zsh-purpleblood-theme/) - Based on [darkblood](https://github.com/ohmyzsh/ohmyzsh/blob/master/themes/darkblood.zsh-theme). Includes decorators for `username@host`, `git` status, and current directory.
-- [purr](https://github.com/mubinben/purr-zsh-theme) - Includes decorators for username, current directory and `git` information.
 - [purs](https://github.com/xcambar/purs) - A fast [pure](https://github.com/sindresorhus/pure)-inspired prompt written in [Rust](https://www.rust-lang.org/).
 - [pustelto](https://github.com/Pustelto/shell_theme) - Colorful theme inspired by the [Spaceship](https://github.com/denysdovhan/spaceship-prompt) theme, includes `git` decorations.
 - [pwn](https://github.com/gh05t-4/pwn-theme) - Includes decorators for user@host, `git` & `hg` status, ruby version, python virtualenv and current working directory.