Update class RemoteFile to include property oc:permissions
Populate RemoteFile with permission value
Update RemoteFile and ReadRemoteFolder classes for including the remote_id property
Update parsing of PROPFIND responses to save, if exists, the value of the properties oc:permissions and oc:id
Updated name of constants for extended WebDAV properties
Merge pull request #31 from owncloud/see_files_shared_with_me

Process extra properties oc:permissions and oc:id