minor fixes for freestyle
- update copying code for linestyles to copy gaps
- update copying code for freestyle line modifiers to copy mapping flags and seeds
- fix drawing code for Material modifiers after a recent refactoring


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56298 954f8c5b-7b00-dc11-b283-0030488c597c