README.md in ndr_pseudonymise-0.4.2

- old
+ new

@@ -2,10 +2,25 @@
 
 `ndr_encrypt` encrypts images and other files, allowing them to be hosted and
 retrieved safely. The files still need to be hosted securely, but public /
 private key encryption provides additional protection.
 
+## Installation
+
+Add this line to your application's Gemfile:
+
+```ruby
+gem 'ndr_pseudonymise'
+```
+
+or for command line usage only, without installing any gems:
+
+``` shell
+$ git clone https://github.com/NHSDigital/ndr_pseudonymise.git
+$ ndr_pseudonymise/script/ndr_encrypt/ndr_encrypt --help
+```
+
 ## Overview
 
 We define a simple suite of tools, `ndr_encrypt`, to generate the encrypted
 image files, and the data that lets us access them. These work in a similar way
 to git object storage, and require minimal software to run in a standard Linux
@@ -79,9 +94,11 @@
 bWE9MC40NTQ1NDUALAAAAAAMAAgAAAITjI8HC9GuTJvozRchVQz6BIZgAQA7
 BASE64
 
 # Add the object to the repository
 ndr_encrypt add --key_name=ourkey1 --pub_key=ourkey1.pub test/dir/ok.gif
+# or add the directory contents recursively
+# ndr_encrypt add --key_name=ourkey1 --pub_key=ourkey1.pub test
 
 # Move aside the original file, to test recovery
 mv test/dir/ok.gif{,.orig}
 
 # Recover file from the repository, prompting for the passphrase