Change approach to what goes into this .gitignore

For a long time, I put rules for things like macOS ~/.DS_Store files,
Emacs backup files, and similar stuff into every project's .gitignore
file. Now I've come to the conclusion this is suboptimal. Instead,
project-specific .gitignore files should only include what's specific
to the given project, and for things like people's backup files or
os-specific things, people should configure their git installation to
use a global excludes file. Turns out that this is the practice
recommended in GitHub's own documentation and some other people, e.g.,
https://augustl.com/blog/2009/global_gitignores/

Author: mhucka

.gitignore

@@ -1,72 +1,31 @@
-# -*- sh -*-
-
-# Compiled source
-# .............................................................................
-
-*.com
-*.class
-*.dll
-*.exe
-*.o
-*.so
-*.dylib
-
-# Compressed archives & package files
-# .............................................................................
-
-*.7z
-*.dmg
-*.gz
-*.iso
-*.jar
-*.rar
-*.tar
-*.zip
-
-# OS-specific things to ignore:
-# .............................................................................
-
-.DS_Store
-.DS_Store?
-._*
-.Spotlight-V100
-.Trashes
-ehthumbs.db
-Thumbs.db
-
-# Dropbox and similar files to ignore:
-# .............................................................................
-
-.dropbox
-
-# Emacs-specific things to ignore:
-# .............................................................................
-
-*~
-.\#*
-\#*\#
-.git/COMMIT_EDITMSG
-auto
-*.synctex.gz
-TAGS
-
-# LaTeX-specific things to ignore:
+# =========================================================== -*- gitignore -*-
+# @file    .gitignore
+# @brief   Files and patterns for files and subdirs that git should ignore
+# @date    %CREATION_DATE%
+# @license Please see the file named LICENSE in the project directory
+# @website https://github.com/caltechlibrary/%PROJECT_URLNAME%
+#
+# The approach we suggest is to add ONLY project-specific rules here. Put
+# rules that apply to your way of doing things (and the particular tools you
+# happen to use) into a global git ignore file as described in the section
+# "Configuring ignored files for all repositories on your computer" here:
+# https://docs.github.com/en/get-started/getting-started-with-git/ignoring-files
+# (accessed on 2022-07-14). For example, Emacs checkpoint and backup files are
+# things that are not specific to a given project; rather, Emacs users will
+# see them created everywhere, in all projects, because they're a byproduct
+# of using Emacs, not a consequence of working on a particular project. Thus,
+# they belong in a user's global ignores list, not in this project .gitignore.
+#
+# A useful starting point for global .gitignore file contents can be found at
+# https://github.com/github/gitignore/tree/main/Global (as of 2022-07-14).
+# =============================================================================
+
+# Ignore backup files created by our Makefile
 # .............................................................................
 
-*.aux
-*.bbl
-*.blg
-*.fls
-*.loc
-*.lof
-*.log
-*.lot
-*.mp
-*.out
-*.toc
-*.toc
+*.bak
 
-# Python-specific things to ignore:
+# Python-specific things to ignore (relevant because this is a Python project).
 # .............................................................................
 
 __pycache__/
@@ -76,23 +35,3 @@ __pycache__/
 .eggs/
 .pytest_cache
 .coverage
-
-# InnoSetup-specific things to ignore:
-# .............................................................................
-
-*.~is
-
-# Jupyter Notebook-specific things to ignore:
-# .............................................................................
-
-.ipynb_checkpoints
-
-# Ignore some common backup file patterns:
-# .............................................................................
-
-*.bak
-
-# Project-specific things to ignore:
-# .............................................................................
-
-README.md.tmp