Add file system watch method display in status

I have had some confusion previously as to whether I was using polling
or notification that this would have helped clarify.
This display will indicate whether polling or notification is being
used.
Merge pull request #68 from acant/feature/fs_watch_status

Add file system watch method display in status
Bump version to 0.5.0
Bump to version 0.5.0.pre1