Add buttons documentation

- Add documentation for how to use buttons
- Update markup and CSS rulesets to support icons on the left or the
right of text

Signed-off-by: Derick Montague <derick.montague@ibm.com>
Change-Id: Ic897f416e85824287360bc7ef5dc47c402d64eba
diff --git a/src/components/Global/InputPasswordToggle.vue b/src/components/Global/InputPasswordToggle.vue
index 3199cab..40fb744 100644
--- a/src/components/Global/InputPasswordToggle.vue
+++ b/src/components/Global/InputPasswordToggle.vue
@@ -52,6 +52,7 @@
 
   svg {
     margin-left: 0;
+    vertical-align: sub;
   }
 }
 </style>