[IMP] fields: update inverse fields lazily for performance

When a relational field is assigned in an onchange, its inverse field is
updated in cache.  Reading the current value of the inverse field may be
costly, for instance in the case of a one2many field with thousands of records
as a value.  Instead, put in cache a SpecialValue that reads and updates the
field; it will be triggered only when it is accessed.
[IMP] models: do not prefetch too many records at once
[IMP] models: prefetch fields with groups (those to which user has access)
[REF] Packaging: moved all the windows-related files into an unique win32 directory + cleanup
[FIX] config.py: do not use appsdir to define the user's data dir when he has no home directory on unix

Force it to be '/var/lib/(appname)' in this case
[REF] Renamed files whose names contained whitespaces
[REF] setup: cleanup and linting of setup.py, reworked MANIFEST, added requirements.txt
[REF] Debian: renamed debhelpers scripts to not contain openerp in their filenames anymore, removed run_all_with_tests.sh script
[FIX] Debian: updated informations and dependencies, refactored debhelpers scripts to allow easy name change, simplified debhelper rules
[ADD] RedHat: defined the dependencies and added a post-install script to create the odoo user, the odoo configuration file, ...
[REF][FIX]: Windows packaging: lint, cleanup and make it work

setup.nsi: make it build and use postgresql 9.3
win32_se*: lint and simplified
Makefile: only one mode
[REF] Package.py: refactoring including cleanup, lint, and use of docker to test unix releases
Forward port of branch saas-5 up to 9a7f48a
[ADD] add new test for onchange on one2many field
[FIX] Windows packaging: correct Makefile.version writing and remove useless lib installation
[FIX] web: chain close action on wizard confirm

If a wizard has several steps, or laucnh a second wizard, the view from where has been loaded the initial wizard is finally reloaded
[IMP] Optimize the schedulers of the calendar, fetchmail and base_action_rules modules

Disable the the crons when they'd have nothing to do, re-enable them when a
task is (probably) introduced
[FIX] account_payment: lin2bank correct fallback condition
[FIX] im_chat : scroll down on opening conversation and add scroll bar on user list
[FIX] im_chat : use direct sql query on im_search method for perfomance issue
 and fix away status