Add json output flag (#139)

README.md

@@ -12,8 +12,9 @@
   - [View Hot Deals](#view-hot-deals)
   - [View and Sort Hot Deals](#view-and-sort-hot-deals)
   - [Search](#search)
-    - [Advanced](#advanced)
+    - [Regex](#regex)
   - [View Posts](#view-posts)
+  - [JSON Output](#json-output)
 - [Shell Completion](#shell-completion)
   - [bash](#bash)
   - [zsh](#zsh)
@@ -47,7 +48,6 @@ If you have [brew](https://brew.sh):
 brew install davegallant/public/rfd
 ```
 
-
 ## Usage
 
 All commands open up in a [terminal pager](https://en.wikipedia.org/wiki/Terminal_pager).
@@ -93,7 +93,7 @@ rfd threads --sort-by views --pages 10
 rfd search 'pizza'
 ```
 
-#### Advanced
+#### Regex
 
 Regular expressions can be used for search.
 
@@ -111,6 +111,16 @@ rfd posts https://forums.redflagdeals.com/kobo-vs-kindle-2396227/
 
 This allows for easy grepping and searching for desired expressions.
 
+### JSON Output
+
+All commands support JSON output.
+
+For example:
+
+```sh
+rfd threads --output json
+```
+
 ## Shell Completion
 
 Shell completion can be enabled if using `bash` or `zsh`.