[changed] PaginationButton to use SafeAnchor

Using the `SafeAnchor` for better accessibility.

Per react-bootstrap#786 commitcomment-11527424
Resolves react-bootstrap#788

Author: mtscout6

src/PaginationButton.js

@@ -2,6 +2,7 @@ import React from 'react';
 import classNames from 'classnames';
 import BootstrapMixin from './BootstrapMixin';
 import createSelectedEvent from './utils/createSelectedEvent';
+import SafeAnchor from './SafeAnchor';
 
 const PaginationButton = React.createClass({
   mixins: [BootstrapMixin],
@@ -25,24 +26,29 @@ const PaginationButton = React.createClass({
   },
 
   handleClick(event) {
-    // This would go away once SafeAnchor is available
-    event.preventDefault();
-
     if (this.props.onSelect) {
       let selectedEvent = createSelectedEvent(this.props.eventKey);
       this.props.onSelect(event, selectedEvent);
     }
   },
 
   render() {
-    let classes = this.getBsClassSet();
+    let classes = {
+      active: this.props.active,
+      disabled: this.props.disabled,
+      ...this.getBsClassSet()
+    };
 
-    classes.active = this.props.active;
-    classes.disabled = this.props.disabled;
+    let {
+      className,
+      ...anchorProps // eslint-disable-line object-shorthand
+    } = this.props;
 
     return (
-      <li className={classNames(this.props.className, classes)}>
-        <a href='#' onClick={this.handleClick}>{this.props.children}</a>
+      <li className={classNames(className, classes)}>
+        <SafeAnchor
+          {...anchorProps}
+          onClick={this.handleClick} />
       </li>
     );
   }