Add star button to starred list to directly remove favorites

This addresses issue #2 .
There might be an issue with this line, while checking a different plugin, I got the following warning in the apache error.log:

[Mon Nov 24 15:54:13.452076 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP Warning:  substr() expects parameter 1 to be string, array given in /home/michael/IdeaProjects/dokuwik
i/lib/plugins/starred/action.php on line 39, referer: http://127.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452130 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP Stack trace:, referer: http://127.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452170 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   1. {main}() /home/michael/IdeaProjects/dokuwiki/doku.php:0, referer: http://127.0.0.1/~michael/dokuw
iki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452177 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   2. act_dispatch() /home/michael/IdeaProjects/dokuwiki/doku.php:119, referer: http://127.0.0.1/~micha
el/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452187 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   3. Doku_Event->advise_before() /home/michael/IdeaProjects/dokuwiki/inc/actions.php:32, referer: http
://127.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452197 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   4. Doku_Event_Handler->process_event() /home/michael/IdeaProjects/dokuwiki/inc/events.php:67, refere
r: http://127.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452206 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   5. action_plugin_starred->handle_action_act_preprocess() /home/michael/IdeaProjects/dokuwiki/inc/eve
nts.php:204, referer: http://127.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760
[Mon Nov 24 15:54:13.452214 2014] [:error] [pid 30114] [client 127.0.0.1:36755] PHP   6. substr() /home/michael/IdeaProjects/dokuwiki/lib/plugins/starred/action.php:39, referer: http://1
27.0.0.1/~michael/dokuwiki/doku.php?id=start&do=edit&rev=1416840760