create-db script test a mysql connection. Delete user/pass if it fails

 - So a new user/password could be created
Database operations at create-db splited

 - Thus if any of them fails, the other will also be executed
Updated changelog
dovecot master password configuration
generate master password to be used from SOGo to access imap
add and complete doc to methods
add dovecot-sqlite dependency to mail module
mkdir -p of samba's private mapistore dir
Merge branch 'master' into jgarcia/set-masterpwd-for-dovecot
change name of master password file
Avoid unsaved changes after running initialSetup
Merge branch 'mjulian/safer-create-db-script'

Conflicts:
	main/core/ChangeLog
Merge pull request #1207 from Zentyal/jag/mail-initial-setup-avoid-changes

Avoid unsaved changes after running initialSetup
Merge branch 'master' into jgarcia/set-masterpwd-for-dovecot

Conflicts:
	main/mail/ChangeLog
Merge branch 'jgarcia/set-masterpwd-for-dovecot'
releasing mail 3.4.1
added missing changelog entry in last PR
force depend on new mail version
releasing openchange 3.4.1
Bumping version to fix the upgrade