Update res/values-fr/strings.xml
Don't create Message objects when changing flags of selected messages

This changes the interface to MessagingController and the way flags are
updated in the database. Now messages aren't changed one by one but in
batches of 500. This should give better performance, but breaks the
unread and flagged count. I'm not very sad about this, because now we
can move towards only displaying the number of unread/flagged messages
in the local database.
Add an "empty view" to the message list

This will display a spinning progress indicator while the message list
is loaded from the database.
Refresh the list when returning to the message list activity
Fix "up" logic in MessageList

Fixes issue 4727
Merge pull request #214 from jacky672/patch-1

Update res/values-fr/strings.xml
Remove the progress spinner when not in use so that the "Load more..." text is centered.
Strip RE/FW from the MessageList subject line for thread subjects.

"Be like Outlook."
Only count local messages for unread/flagged count

Currently only the Accounts activity uses the new count.

While working on this I realized that the unread/flagged search for
accounts currently looks for unread/flagged messages in all folders, not
all displayable folders without special folders (Trash, Spam, Outbox,
Sent, Drafts) like we used to.
Also, the "All messages" search currently doesn't limit the search to
searchable folders like it is supposed to.
Restore behavior of unread/flagged filtered message list

The unread/flagged count/view for accounts now excludes special folders
and only includes displayable folders as specified by the display class.
Only list messages in searchable folders under "All messages"
Remove leading space in action bar title of Accounts activity
Retain unread count in Accounts activity during configuration changes
Set action bar title for Accounts activity in onCreate()
Update res/values-el/strings.xml

Translation of 4 new strings
Use constant "UUID" for search accounts

This way we can match the account stats to the search accounts when the
Accounts activity is restarted.
Refresh action bar title in FolderList when unread count was calculated
Use local unread/flagged count in folder list and message list
Remove all code using the old unread/flagged count database columns
Remove unused methods