chore(readme): add badges (#3)

- TravisCI
- Coveralls
- David for dependencies
- semantic-release

README.md

@@ -1,13 +1,19 @@
 # Stats reporting plugin for webpack
 
+[![Build Status](https://travis-ci.com/brandondoran/stats-reporter-webpack-plugin.svg?branch=master)](https://travis-ci.com/brandondoran/stats-reporter-webpack-plugin)
+[![Coverage Status](https://coveralls.io/repos/github/brandondoran/stats-reporter-webpack-plugin/badge.svg?branch=master)](https://coveralls.io/github/brandondoran/stats-reporter-webpack-plugin?branch=master)
+[![dependencies Status](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin/status.svg)](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin)
+[![devDependencies Status](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin/dev-status.svg)](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin?type=dev)
+[![peerDependencies Status](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin/peer-status.svg)](https://david-dm.org/brandondoran/stats-reporter-webpack-plugin?type=peer)
+[![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release)
 [![Greenkeeper badge](https://badges.greenkeeper.io/brandondoran/stats-reporter-webpack-plugin.svg)](https://greenkeeper.io/)
 
 Send the stats of a build to a reporting service. Currently DataDog is the only reporter implemented.
 
 ## Installation
 
 ```sh
-$ npm install --save-dev stats-reporter-webpack-plugin
+npm install --save-dev stats-reporter-webpack-plugin
 ```
 
 ## Usage
@@ -38,7 +44,7 @@ module.exports = {
 new StatsReporterPlugin(options: StatsReporterPluginOptions);
 ```
 
-##### DataDogStatsReporterOptions fields
+#### StatsReporterPluginOptions fields
 
 - `reporter: StatsReporter`: The reporter to use for sending stats.
 
@@ -56,6 +62,6 @@ new DataDogStatsReporter(options: DataDogStatsReporterOptions);
 - `gzipSize?: boolean = true`: Report gzipped size if true, uncompressed size if false
 - `metricName: string`: The base name for the metric
 - `tags?: string[]`: Custom tags for the metric. The following tags are always added:
-  * `chunk`: the chunk name
-  * `type`: the type of asset (js, css, etc)
+  - `chunk`: the chunk name
+  - `type`: the type of asset (js, css, etc)
 - `test?: RegExp`: Test to match files against. If not set, stats for all emitted assets will be sent.