More pages are fixed now

Hi, folks!

Today, I have fixed all the links into the following forums:

                - Folk Bands
                - Folk Discussion
                - The Gallery (registered users only)
                - Musicians search
                - Musicians

Also, I've fixed links of the instruments pages to the homepage of the folk elements project. Left bands threads links to fix there but I have to wait for one update from the forum's firm which will delete the bugs.