Add option to create temp parent folder (for a fresh CInbox)

[pjotrek-b]

Initial creation of processing folders using --init parameter (see #40) works great:

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Newly created 5 processing folders. Have fun!
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But fails right afterwards, because the temp parent folder /var/cinbox doesn't exist (yet):

Temporary folder: '/var/cinbox/ci-fes_adsd_audio_dat'
PHP Warning:  mkdir(): No such file or directory in /home/arkthis/install/cinbox-fes-av/src/lib/CInbox/CInbox.php on line 741
ERROR  Could not create temp folder '/var/cinbox/ci-fes_adsd_audio_dat'. Check access rights? Does parent folder exist?
ERROR  Could not init Inbox due to errors:

ERROR  mkdir(): No such file or directory[/home/arkthis/install/cinbox-fes-av/src/lib/CInbox/CInbox.php:741]

Clean ending of Inbox...

TODO: Create parent temp-folder when --init is used.

[pjotrek-b]

NOTE: permissions for /var/cinbox must allow write access by the user/group cinbox will be running as.