Change js incrementing order of objects displayed in Gallery.
Change js incrementing order of objects displayed in Gallery.

Ticket #247 @ zena3. It was impossible to swap order of 
2 GalleryItems due to IntegrityError 1062
"Duplicate entry <Gallery_id>-<GalleryItem_id> for key <GalleryItem_id>."
Order fields are prepopulated with increment.js.
Order increment is set to 10 now, so "swapping" can be done by
increment/decrement order to a vacant index.


git-svn-id: 6ce22b13eace8fe533dbb322c2bb0986ea4cd3e6@700 2d143e24-0a30-0410-89d7-a2e95868dc81

WhiskeyMedia/ella,whalerock/ella,MichalMaM/ella,whalerock/ella,petrlosa/ella,petrlosa/ella,WhiskeyMedia/ella,MichalMaM/ella,whalerock/ella,ella/ella