Add a slides type to new_tex_document

Extraction now takes the whole tree and copies the template out with
tar -h, so symlinks into resources/ arrive as real files rather than as
links pointing outside the new document.

new_beamer_presentation is superseded; cdsc_tex_aliases.sh keeps the name
as an alias.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

slides_template/new_beamer_presentation

@@ -1,43 +0,0 @@
-#!/bin/sh
-
-# Helper script to export LaTeX templates for new documents
-# Copyright (c) 2009-2022 Benjamin Mako Hill <mako@atdot.cc>
-# Released under the GPLv3 or later.
-
-set -e
-
-SOURCEDIR="$HOME/tex/beamer-mako"
-CURDIR=$(pwd)
-
-if [ -n "$1" ]
-then
-    if [ -e "$1" ]; then
-        echo "error: '$1' already exists"
-        exit 1
-    fi
-
-    WORK_DIR=$(mktemp -d)
-    cd "$SOURCEDIR"
-    git archive --format=tar HEAD template | tar x --strip=1 -C "$WORK_DIR"
-    cd "$CURDIR"
-    mv "$WORK_DIR" "$1"
-
-    mv "$1/example.tex" "$1/$(basename "$1").tex"
-
-    # create a symlink farm for the fonts
-    cd "$1"
-    rm -rf ./fonts/*
-
-    # first create the directories
-    for fontdir in "${SOURCEDIR}/template/fonts/"*; do
-        mkdir "./fonts/$(basename "${fontdir}")"
-        # then the files
-        for fontfile in "${fontdir}/"*; do
-            ln -s "${fontfile}" "./fonts/$(basename "${fontdir}")/$(basename "${fontfile}")"
-        done
-    done
-
-    cd "$CURDIR"
-else
-    echo "specify a directory where the template should go"
-fi