Add Cat A File With Line Numbers as a zsh til.

README.md

@@ -107,6 +107,7 @@ smart people at [Hashrocket](http://hashrocket.com/).
 
 ### zsh
 
+- [Cat A File With Line Numbers](zsh/cat-a-file-with-line-numbers.md)
 - [Clear The Screen](zsh/clear-the-screen.md)
 - [Create A File Descriptor with Process Substitution](zsh/create-a-file-descriptor-with-process-substitution.md)
 - [Killing A Frozen SSH Session](zsh/killing-a-frozen-ssh-session.md)

zsh/cat-a-file-with-line-numbers.md

@@ -0,0 +1,27 @@
+# Cat A File With Line Numbers
+
+You can quickly view a file using `cat`
+
+```
+$ cat Gemfile
+source 'https://rubygems.org'
+
+
+# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
+gem 'rails', '4.2.0'
+# Use postgresql as the database for Active Record
+gem 'pg'
+```
+
+With the `-n` flag I can view that file with line numbers
+
+```
+$ cat -n Gemfile
+ 1  source 'https://rubygems.org'
+ 2  
+ 3  
+ 4  # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
+ 5  gem 'rails', '4.2.0'
+ 6  # Use postgresql as the database for Active Record
+ 7  gem 'pg'
+```