Update standard to version 8.4.0

https://github.com/feross/standard/blob/master/CHANGELOG.md

8.4.0 - 2016-10-10

Update ESLint from 3.6.x to 3.7.x.
5 additional rules are now fixable with standard --fix!
Use more conservative semver ranges #654
8.3.0 - 2016-09-29

The last release (8.2.0) added ES7 support. This release (8.3.0) adds
ES8 support ...just 3 days later!

This release should eliminate the need to specify babel-eslint as a
custom parser, since standard can now parse ES8 (i.e. ES2017) syntax
out of the box. That means async and await will just work.

Support ES8 (i.e. ES2017) syntax.
8.2.0 - 2016-09-26

For many users, this release should eliminate the need to specify
babel-eslint as a custom parser, since standard can now parse ES7 (i.e.
ES2016) syntax out of the box.

Support ES7 (i.e. ES2016) syntax.
Update ESLint from 3.5.x to 3.6.x.
4 additional rules are now fixable with standard --fix!
8.1.0 - 2016-09-17

Update ESLint from 3.3.x to 3.5.x.
Around 10 additional rules are now fixable with standard --fix!
8.0.0 - 2016-08-23

This release contains a bunch of goodies, including new rules that
catch potential programmer errors (i.e. bugs) and enforce additional
code consistency.

However, the best feature is surely the new --fix command line flag to
automatically fix problems. If you ever used standard-format and ran
into issues with the lack of ES2015+ support, you'll be happy about
--fix.

standard --fix is built into standard v8.0.0 for maximum convenience,
it supports ES2015, and it's lightweight (no additional dependencies
since it's part of ESLint which powers standard). Lots of problems are
already fixable, and more are getting added with each ESLint release.

standard also outputs a message ("Run standard --fix to automatically
fix some problems.") when it detects problems that can be fixed
automatically so you can save time!

With standard v8.0.0, we are also dropping support for Node.js versions
prior to v4. Node.js 0.10 and 0.12 are in maintenance mode and will be
unsupported at the end of 2016. Node.js 4 is the current LTS version.
If you are using an older version of Node.js, we recommend upgrading to
at least Node.js 4 as soon as possible. If you are unable to upgrade to
Node.js 4 or higher, then we recommend continuing to use standard v7.x
until you are ready to upgrade Node.js.

Important: We will not be updating the standard v7.x versions going
forward. All bug fixes and enhancements will land in standard v8.x.

Full changelog below. Cheers!

New features

Upgrade to ESLint v3
(http://eslint.org/docs/user-guide/migrating-to-3.0.0) #565
BREAKING: Drop support for node < 4 (this was a decision made by the
ESLint team)
Expose ESLint's --fix command line flag #540 standard-engine/#107
Lightweight, no additional dependencies, fixes dozens of rules
automatically
New rules

(Estimated % of affected standard users, based on test suite in parens)

Enforce placing object properties on separate lines
(object-property-newline) #524 (2%)
Require block comments to be balanced (spaced-comment "balanced") #572
(2%)
Disallow constant expressions in conditions (no-constant-condition)
#563 (1%)
Disallow renaming import, export, and destructured assignments to the
same name (no-useless-rename) #537 (0%)
Disallow spacing between rest and spread operators and their
expressions (rest-spread-spacing) #567 (0%)
Disallow the Unicode Byte Order Mark (BOM) (unicode-bom) #538 (0%)
Disallow assignment to native objects/global variables
(no-global-assign) #596 (0%)
Disallow negating the left operand of relational operators
(no-unsafe-negation) #595 (0%)
Disallow template literal placeholder syntax in regular strings
(no-template-curly-in-string) #594 (0%)
Disallow tabs in file (no-tabs) #593 (0%)
Changed rules

Relax rule: Allow template literal strings (backtick strings) to avoid
escaping
 #421
Relax rule: Do not enforce spacing around * in generator functions
(standard/standard#564 (comment))
This is a temporary workaround for babel users who use async generator
functions.

package.json

@@ -29,7 +29,7 @@
     "grunt-shell": "^1.3.0",
     "node-sass": "^3.2.0",
     "readdir": "0.0.6",
-    "standard": "^7.1.2"
+    "standard": "^8.4.0"
   },
   "scripts": {
     "test": "standard && grunt test && npm run lint --silent",