When removing Odoo Debian package, the directory /var/lib/odoo is also
removed. This directory could contain important data like filestore or
custom modules.

With this commit, this directory is preserved on removal and deleted
when the purge command is issued with a Debian package manager.

Fixes #22138

[REF] Packaging: backport of a7ab5a41
[REF] Packaging: backport of a700a113
[REF] Packaging: backport of 9d0bd280
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[REF] Packaging: backport of cc113317
[FIX] Packaging: backport of 13471630
[REF] Package: backport of 93845d68
[REF] Package: backport of 012bc01c
[FIX] Package: partial apply of d9e72a37
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[REF] Package: backport of 2f4984b8
[REF] Package: backport of 6e9edeeb
[REF] Package: partial backport of d4624fa8
[REF] Package: backport of 9f13722f

[FIX] Debian: updated informations and dependencies, refactored debhelpers scripts to allow easy name change, simplified debhelper rules

[REF] Debian: renamed debhelpers scripts to not contain openerp in their filenames anymore, removed run_all_with_tests.sh script

- move packaging stuff to setup
- remove historical stuff
- remove oe, odoo-cmd-fme will be merged with the convered commands
- add an odoo.py script to run odo and boostrap it
- simplify README
- prepare to move documentation to the github wiki

bzr revid: vmt@openerp.com-20130227161101-mzz3wluzrez7l74n

bzr revid: vmt@openerp.com-20130227142420-295yua6tyfalaido

bzr revid: al@openerp.com-20111006001810-ew5fm6w2lsr790xy

bzr revid: al@openerp.com-20111001162731-6cqw1usxrb6045vl