Skeleton code.
Update the last known file size & write time.
List -> Dict
Watcher working for the basic stuffs.
Entry addition, change, deletion sort of works.
Defer the external deletion processing to see if there is any following changes to the same file.
Move the Watcher_PhotoChanged method down.
Removed all the unnecessary properties that are added.
Moved lots of exception handling code to EntryWatcher
Photos are updated correctly.
Reduced the abrupt list scroll position change when an external change is detected.
Merge branch 'feature/monitoring_changes(#4)' into develop