Merge pull request #256 from terraform/upd-markdown

updated markdown to add script to remove existing gpg keys

docs/how-to/git/add-user-to-git-secret.md

@@ -1,4 +1,4 @@
-# How to add a user to git-secret
+# Managing users in git-secret
 
 This describes the steps to add a user's GPG key to the main `support` keyring, as well as how to add it to the
 `git-secret` setup in each account.
@@ -93,6 +93,19 @@ in merge conflicts and more work figuring out what has actually changted.
 
 In your PR, please include the output of the `gpg {USERNAME}.gpg.asc` in the Pull Request text.
 
+## Remove user access from git-secret 
+
+The below is an example.
+
+```script
+git-secret reveal -f
+cd init/git-secret
+git-secret removeperson roy.d.ashley.jr@census.gov
+git-secret removeperson patrick.o.ibekwe@census.gov
+git rm ashle001*asc ibekw001*asc
+./setup-git-secret.sh
+git commit -m'remove ashle001 and ibekw001 gpg keys' -a
+```
 ## Using the updated encrypted files
 
 Once it is merged, you can inform the user, and they refresh and reveal in order to use the unecrypted files.