Default 'end time' for new canvases to 5s instead of 0. That's one less thing a...

Default 'end time' for new canvases to 5s instead of 0.  That's one less thing a new user then needs to edit to start making his first animation.  Also, don't show the intimidating canvas properties dialog when a layer is created, just use the defaults.  Set environment variable "SYNFIG_ENABLE_NEW_CANVAS_EDIT_PROPERTIES" to revert this change locally.  See synfig.org/Wish_list#Improved_User_Experience_for_First_Contact .

git-svn-id: http://svn.voria.com/code@1519 1f10aa63-cdf2-0310-b900-c93c546f37ac