3D

This patch adds database and template support for a 3D property for movies. Some notes:

1) The 3D information does not get fetched by the engines. There is a new checkbox in the edit pages instead.

2) NexGen already had a "checkbox" for 3D but it seemed to me, that the property did not get saved (changing it made no difference at all, the value was lost upon saving). I simply renamed that property to make use of the new one that gets persisted.

3) I have absolutely no idea if this is the way to introduce a new field into the database, i.e. if the install and upgrade files are correct. The SQL works but someone needs to check if the rest is ok ;-)

4) In the elegant template, instead of displaying only the text "3D", you can add an icon to "templates/elegant/images" called "3d.gif" and it will be used instead. Since I am not great at creating icons and I'm not sure about the state of copyright when it comes to icons, I did not include one in the patch itself (actually I did and it was quite a hassle to get rid of it again ;-))

5) Since I am not using all of the features, videodb has gathered over the years I am not sure if there might be another place this needs to be integrated into.

EDIT: I don't know why this pull request features 39 commits now...could have something to do with me deleting the icon from the repository?! I don't know. The changes in "Changed files" seem to be ok though.