Port file-sync plugin to latest API changes
Port file-sync plugin to latest API changes

 - osync_rand_str got OSyncError** parameter
 - OSyncMarshal API changes, see r5780



git-svn-id: d6e11ae9e9475c467509976a7018c625922d636e@5782 53f5c7ee-bee3-0310-bbc5-ea0e15fffd5e

luizluca/opensync-file-sync,luizluca/opensync-file-sync