Coding standards.
IMoveTarget support in the object tree.
Removed ObjectTree and Tree\FileSystem

The distinction between ObjectTree and Tree\FileSystem was an extremely
rarely used extension point.

With the advent of IMoveTarget, Tree\FileSystem also becomes unneeded.
Merge branch 'master' into move
Merge branch 'master' into move
Merge branch 'master' into move

Conflicts:
	lib/DAV/FSExt/Directory.php
	lib/DAV/ObjectTree.php
	lib/DAV/Tree.php
	lib/DAV/Tree/Filesystem.php
Fixed unittest.
Merge branch 'master' into move
moveInto is fully tested.
Small typo.
Updated changelog.
Merge pull request #522 from fruux/move

moveInto support