Tweak and elaborate on language names

Closes #94. Closes #137.

Author: jstrieb

README.md

@@ -47,18 +47,21 @@ would be unable to access.
 
 The GitHub statistics API returns inaccurate results in some situations:
 
-- Total lines of code modified may be inflated – GitHub counts changes to files
-  like `package-lock.json` that may impact the line count in surprising ways
+- Total lines of code modified may be too high or too low
+  - GitHub counts changes to files like `package-lock.json` that may inflate the
+    line count in surprising ways
   - On the other hand, GitHub refuses to count lines of code for repositories
     with more than 10,000 commits, so contributions to those will not be
     reflected in the data at all
   - [The GitHub API endpoint for computing contributor statistics no longer
     works reliably](https://github.com/orgs/community/discussions/192970), so we
-    compute the statistics ourselves by cloning each repository locally and
-    tallying lines changed with the `git` CLI
+    fall back on computing the statistics ourselves by cloning each repository
+    locally and tallying lines changed with the `git` CLI
     - Our computed totals likely under-count relative to GitHub's, since theirs
       correctly attribute authorship for contributions to pull requests with
       several authors that end up squashed and merged by just one author
+    - They also correctly attribute commits we may miss if they are made with
+      old email addresses no longer connected to the account
 - Repository view count statistics often seem too low, and many referring sites
   are not captured
   - If you lack permissions to access the view count for a repository, it will
@@ -84,8 +87,8 @@ and retrieve the images.
    and `repo`
    permissions.](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/managing-your-personal-access-tokens)
    1. [Navigate to the personal access tokens (classic)
-      page.](https://github.com/settings/tokens) Open that link in a new tab,
-      or proceed with the steps below.
+      page.](https://github.com/settings/tokens) Open that link in a new tab, or
+      proceed with the steps below.
       1. Click your avatar in the top right corner, then "Settings" on the menu
          that drops down.
       1. Click "Developer settings" from the menu on the left.
@@ -105,17 +108,17 @@ and retrieve the images.
    1. **Copy the token and save it somewhere.** If you lose it, you will not be
       able to access it again, and will have to regenerate a new one. I keep
       mine saved along with the GitHub entry in my password manager.
-   1. Some users report that it can take some time for the personal access
-      token to take effect. For more information, see
+   1. Some users report that it can take some time for the personal access token
+      to take effect. For more information, see
       [#30](https://github.com/jstrieb/github-stats/issues/30).
 1. Create a copy of this repository by clicking
    [here](https://github.com/jstrieb/github-stats/generate).
    - Equivalently, click the big, green "Use this template" button at the top
      left of the page, then click "Create a new repository."
    - Note: this is **not** the same as forking a copy because it copies
      everything fresh, without the huge commit history.
-1. Create a new repository secret named `ACCESS_TOKEN` with your personal
-   access token from the first step.
+1. Create a new repository secret named `ACCESS_TOKEN` with your personal access
+   token from the first step.
    1. [Go to the "New secret" page for your copy of this repository by clicking
       this link.](../../settings/secrets/actions/new)
       - If the link doesn't work, try clicking it from your copy of this
@@ -132,10 +135,17 @@ and retrieve the images.
 1. (Optional) Make other secrets for more configuration.
    - To exclude some repositories from the aggregate statistics, add them
      (separated by commas) to a secret called `EXCLUDE_REPOS`.
+     - To prevent your copy of this repository from showing up in your
+       statistics, add the name of your copy of the repo to this list.
    - To exclude some languages from the aggregate statistics, add them
      (separated by commas) to a secret called `EXCLUDE_LANGS`.
+     - The languages are case insensitive, and can include spaces.
+     - Language names can be found either in a [local stats file generated by
+       the CLI](#list-languages), or in the [list used by GitHub
+       linguist](https://github.com/github-linguist/linguist/blob/537297cdae3ab05f8d5dd1c03627a5bd73707b19/lib/linguist/languages.yml)
+       (which powers their language analysis on the back end).
    - Lists for `EXCLUDE_REPOS` and `EXCLUDE_LANGS` can use globbing patterns.
-     For example, to exclude all repos by "@jstrieb", add `jstrieb/*` to
+     For example, to exclude all repos by user "jstrieb", add `jstrieb/*` to
      `EXCLUDE_REPOS`.
    - These can also be set directly in [the Actions
      workflow](.github/workflows/main.yml), but you should set them as secrets