started script for storage backend migrations

todo: GCS

added GCS, no GLOBALS, two methods for saving pastes and comments

use GLOBALS for verbosity again

added getAllPastes() to all storage providers

moved to bin, added --delete options, make use of $store->getAllPastes()

added --delete-* options to help

longopts without -- *sigh*

fixed arguments

drop singleton behaviour to allow multiple backends of the same type simultaneously

remove singleton from Model, collapse loop in migrate.php

comments is not indexed

tests without data singleton

fix

exit if scandir() fails

extended meta doc

INSTALL.md

@@ -38,10 +38,10 @@ install and configure PrivateBin on your server. It's available on
 ### Changing the Path
 
 In the index.php you can define a different `PATH`. This is useful to secure
-your installation. You can move the configuration, data files, templates and PHP
-libraries (directories cfg, doc, data, lib, tpl, tst and vendor) outside of your
-document root. This new location must still be accessible to your webserver and
-PHP process (see also
+your installation. You can move the utilities, configuration, data files,
+templates and PHP libraries (directories bin, cfg, doc, data, lib, tpl, tst and
+vendor) outside of your document root. This new location must still be
+accessible to your webserver and PHP process (see also
 [open_basedir setting](https://secure.php.net/manual/en/ini.core.php#ini.open-basedir)).
 
 > #### PATH Example