Merge branch 'theming-improvement' into staging

www/pad/app-pad.less

@@ -1,3 +1,7 @@
+// Defaults to avoid breaking existing themes
+
+@colortheme_pad-toolbar-bg: #c1e7ff;
+
 @import (once) "../../customize/src/less2/include/toolbar.less";
 @import (once) '../../customize/src/less2/include/alertify.less';
 @import (once) '../../customize/src/less2/include/tokenfield.less';

www/poll/app-poll.less

@@ -1,3 +1,9 @@
+// Defaults to avoid breaking existing themes
+
+@colortheme_poll-th-bg: #005bef;
+@colortheme_poll-th-fg: #fff;
+@colortheme_poll-help-bg: #bbffbb;
+
 @import (once) "../../customize/src/less2/include/browser.less";
 @import (once) "../../customize/src/less2/include/toolbar.less";
 @import (once) "../../customize/src/less2/include/markdown.less";