Add /.editorconfig file

The addition of the `/.editorconfig` file is made in order to
encourage and help developers and their teams define and maintain
consistent coding styles between their different editors and IDEs.

By default, `/.editorconfig` includes some basic properties that
reflect the coding styles from the files provided by default, but
users can easily change them to better suit their needs.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Since users need to install a editor/IDE plugin in order for the
properties from the `/.editorconfig` to be applied, we were reluctant
to add this file in the past (see: #1124).
Nowadays however, the EditorConfig project provides plugins for most
of the popular editors/IDEs (see: http://editorconfig.org/#download),
plus, more and more developers are using it.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Ref: http://editorconfig.org/

Close: #1561
       #1564

.editorconfig

@@ -0,0 +1,13 @@
+# editorconfig.org
+
+root = true
+
+[*]
+charset = utf-8
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false

CHANGELOG.md

@@ -1,5 +1,8 @@
 ### HEAD
 
+* Add `/.editorconfig` file
+  ([#1561](https://github.com/h5bp/html5-boilerplate/issues/1561),
+   [#1564](https://github.com/h5bp/html5-boilerplate/issues/1564)).
 * Add `auto` to the Google Universal Analytics tracker create method
   ([#1562](https://github.com/h5bp/html5-boilerplate/issues/1562)).
 * Add `timeline` and `timelineEnd` to the list of `console` methods

doc/misc.md

@@ -4,6 +4,7 @@ table of contents](TOC.md)
 # Miscellaneous
 
 * [.gitignore](#gitignore)
+* [.editorconfig](#editorconfig)
 * [.htaccess](#htaccess)
 * [crossdomain.xml](#crossdomainxml)
 
@@ -32,7 +33,31 @@ globally ignore:
 * Comprehensive set of ignores on GitHub: https://github.com/github/gitignore
 
 
-### `.htaccess`
+## .editorconfig
+
+The `.editorconfig` file is provided in order to encourage and help you and
+your team define and maintain consistent coding styles between different
+editors and IDEs.
+
+By default, `.editorconfig` includes some basic
+[properties](http://editorconfig.org/#supported-properties) that reflect the
+coding styles from the files provided by default, but you can easily change
+them to better suit your needs.
+
+In order for your editor/IDE to apply the
+[properties](http://editorconfig.org/#supported-properties) from the
+`.editorconfig` file, you will need to [install a
+plugin]( http://editorconfig.org/#download).
+
+__N.B.__ If you aren't using the server configurations provided by HTML5
+Boilerplate, we highly encourage you to configure your server to block
+access to `.editorconfig` files, as they can disclose sensitive information!
+
+For more details, please refer to the [EditorConfig
+project](http://editorconfig.org/).
+
+
+### .htaccess
 
 A `.htaccess` (hypertext access) file is a Apache HTTP server configuration
 file. The `.htaccess` file is mostly used for:
@@ -78,7 +103,7 @@ Notice that the original repo for the `.htaccess` file is [this
 one](https://github.com/h5bp/server-configs-apache/blob/master/src/.htaccess).
 
 
-### `crossdomain.xml`
+### crossdomain.xml
 
 The _cross-domain policy file_ is an XML document that gives a web client —
 such as Adobe Flash Player, Adobe Reader, etc. — permission to handle data