Rewrite uses of UIActionSheet

Removed some use of UIActionSheet to use UIActivityViewController.
Where UIActionSheet is still used created if statement for iOS8 to use
UIAlertController
Removed iOS 7 version checks
Fix setting action sheets
Fix activity and action sheet on iPad
Spelling fix
Better entering conversation from notification
Working on SQLCipher passphrase change support
Python script to find unused strings
cleanup script
Fixed deleting messages #251 #265

This is not ideal waiting on ‘Hooks’ which should be in YapDatabase v2.6
Fix saving lastMessageDate when sending message
Merge remote-tracking branch 'origin/master' into sqlcipher_rekey
Redo AutoLayout and remove old passphrase textfield requirement
Changing the db passphrase works
Merge branch 'sqlcipher_rekey' of github.com:chrisballinger/ChatSecure-iOS into sqlcipher_rekey

Conflicts:
	ChatSecure.xcworkspace/xcshareddata/ChatSecure.xccheckout
	ChatSecure/OTRChangeDatabasePassphraseViewController.m
Ignore xccheckout file
Fix setting message delivered
Merge branch 'master' of github.com:chrisballinger/ChatSecure-iOS
Minor tweak to icon, add localized string
Update Tor to v0.2.5.10