feat(btn-group): Adds button groups

src/pivotal-ui/components/alpha/README.md

@@ -1,3 +1,7 @@
 ```html
-<!-- Please put an example here -->
+<div class="btn-group" role="group" aria-label="...">
+  <button type="button" class="btn btn-default">Left</button>
+  <button type="button" class="btn btn-default">Middle</button>
+  <button type="button" class="btn btn-default">Right</button>
+</div>
 ```

src/pivotal-ui/components/alpha/alpha.scss

@@ -1 +1,37 @@
 /* PUT NEW COMPONENTS HERE!!!! */
+@import "../pui-variables";
+
+/*doc
+---
+title: Button Group
+name: button-group
+categories:
+  - Elements
+  - All
+---
+
+<code class="pam">
+<i class="fa fa-download" alt="Install the Component">
+npm install pui-css-buttons-group --save
+</i>
+</code>
+
+Button groups wrap a series of buttons.
+
+```html_example
+<div class="btn-group btn-group-lg" role="group" aria-label="...">
+  <button type="button" class="btn btn-default">Left</button>
+  <button type="button" class="btn btn-default">Middle</button>
+  <button type="button" class="btn btn-default">Right</button>
+</div>
+```
+*/
+
+.btn-group {
+  .btn {
+    &.active, &:active {
+      color: $neutral-11;
+      background-color: $btn-default-color;
+    }
+  }
+}

src/pivotal-ui/components/alpha/package.json

@@ -1,7 +1,8 @@
 {
   "description": "A playground for alpha examples",
-  "homepage": "http://styleguide.pivotal.io/",
+  "homepage": "http://styleguide.pivotal.io/elements#button-group",
   "dependencies": {
+    "pui-css-bootstrap": "1.10.0"
   },
   "version": "0.0.1"
 }