Fixed #448: added some styles to prevent conflicts with bootstrap css styles

gulpfile.js

@@ -81,6 +81,8 @@ gulp.task('bundle-js', ['clean'], function (cb) {
 gulp.task('bundle-css', ['clean'], function () {
   var files = [
     './lib/shared/activator.css',
+    './lib/shared/bootstrap.css',
+
     './lib/timeline/component/css/timeline.css',
     './lib/timeline/component/css/panel.css',
     './lib/timeline/component/css/labelset.css',

lib/shared/bootstrap.css

@@ -0,0 +1,6 @@
+/* override some bootstrap styles screwing up the timelines css */
+
+.vis [class*="span"] {
+  min-height: 0;
+  width: auto;
+}