Added article on JSLint and JSHint indent option

Author: James Allardice

option-articles/indent.md

@@ -0,0 +1,60 @@
+<!---
+{
+    "titles": [
+        "indent"
+    ],
+    "slugs": [
+        "option-indent"
+    ],
+    "linters": [
+        "jslint",
+        "jshint"
+    ],
+    "author": "jallardice",
+    "subject": "option"
+}
+-->
+
+### What does this option do?
+
+In JSLint and JSHint the `indent` option is used to enforce a specific tab width
+in your code. Both tools make their own assumptions about when indentation
+should occur but are largely identical in this regard. In the following example
+we specify an indentation width of 4 spaces. Both tools expect the body of an
+`if` statement to be indented so both will warn if the identation is not of the
+required width:
+
+<!---
+{
+    "linter": "jslint"
+}
+-->
+```javascript
+/*jslint indent: 4 */
+function doSomething(x) {
+    "use strict";
+    if (x) {
+      return;
+    }
+}
+```
+
+### When should I use this option?
+
+With JSLint you'll get an "Expected '{a}' at column {b}, not column {c}" error
+any time an incorrect indentation width is found. In JSHint you'll get an
+"Expected '{a}' to have an indentation at {b} instead at {c}" error under the
+same circumstances. By enabling the validation of indentation you can ensure it
+remains consistent throughout your code which will make it much easier to read.
+Common values for this option are `4` and `2` but the exact number depends on
+your personal preference and existing conventions.
+
+Note that in JSHint this is an *enforcing* option which means JSHint does not
+apply it by default. If you do not explicitly set this option to an integer
+JSHint will not warn about indentation anywhere in your code.
+
+#### Recommendation
+
+ - **JSLint** - Set this option to `2` or `4` to enable indentation validation
+
+ - **JSHint** - Set this option to `2` or `4` to enable indentation validation