Fix event to do not be sent two times

Modified backup was sending two events for list file for same file.

This sometimes hang the software.
Change Settings System

Do not use the default c# system settings anymore, since it didnt' fit
for the cache and other stuff that we do use here. ( including deamons
and other software communication )
Fix sync delete ( when file is deleted )

Fix delete, when reading the cache manifesto, delete the files that
doesn't exist anymore

Add by force the end slash for directories only, both in uri and in
cache manifesto

Create bFile objects even for directories ( better control )

When deleting, add a Service Point config for degub and fine setup

File is last_modified when created also ( windows consider last modified
old date when a file is copied )

Fix directories checking methods, unify them
Refactor some code to be more error prune

$subject,  keep the list clean when start over.

Clean-up when finish
Fix blacklist and delete files

Fix the blacklist and delete files from manifesto.

Also add some basic tests related to files. Add directory node as bFile
object