Add style to general error messages

Resolves #647

src/components/forms/general-error.jsx

 var Formsy = require('formsy-react');
 var React = require('react');
 
+require('./general-error.scss');
+
 /*
  * A special formsy-react component that only outputs
  * error messages. If you want to display errors that
@@ -12,7 +14,7 @@ module.exports = Formsy.HOC(React.createClass({
     render: function () {
         if (!this.props.showError()) return null;
         return (
-            <p className="error">
+            <p className="general-error">
                 {this.props.getErrorMessage()}
             </p>
         );

src/components/forms/general-error.scss

+@import "../../colors";
+
+.general-error {
+    border: 1px solid $active-gray;
+    border-radius: 4px;
+    background-color: $ui-orange;
+    padding: 1rem;
+    color: $type-white;
+}