Update cheatsheets

tldr/modutil

@@ -0,0 +1,17 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# modutil
+
+> Manage PKCS #11 module information within the NSS security module database.
+> More information: <https://manned.org/modutil>.
+
+- Add a PKCS #11 module to a NSS database (e.g. a Firefox profile: `$HOME/.mozilla/firefox/default-release`):
+
+`modutil -dbdir sql:{{path/to/nss/db/dir}} -add "{{module_label}}" -libfile {{path/to/pkcs11_mod.so}}`
+
+- List PKCS #11 modules in a NSS database:
+
+`modutil -dbdir sql:{{path/to/nss/db/dir}} -list`