Make belgian chart of accounts multilingual

This allows it to be translated into Flemish.
The code is based on the code for l10n_ch.
Note that the post install hook 'l10n_be_wizard.yml' has
been replaced with a python hook in 'wizard/account_wizard.py'.
This was done because the yml based hook runs before the
actual translations are loaded and hence fails to
properly translate the chart of accounts.

Lastly, a first, incomplete translation has been included.
Complete translation for chart of accounts, fiscal position, account tax
Merge current ~openerp/openobject-addons/7.0/
[IMP] l10n_multilang: add translation_folder field
[FIX] correctly place blocks
revert changes in translations, done in server
[MERGE] [ADD] l10n_be: l10n_be inherits from l10n_multilang, remove yml for automatic account assignment and replace it by the more common wizard in open state
[ADD] l10n_be: translation belgian accounts templates, courtsey of Geert Janssens
[FIX] l10n_be: can not add new dependency in 7.0 (stable), too bad for multilang
[FIX] l10n_be: trying to cheat runbot into going green, still a data problem with l10n_be_hr_payroll_account
[FIX] l10n_be: move yml file to l10n_be_hr_payroll_account
[FIX] point_of_sale: better default sale journal for new pos.config, use company of current user

done to fix test in 01_order_to_payment.yml when creating pos.order
default config can have journal of different company, will get exception if done with a journal of main company
[FIX] point_of_sale: oups, needs an id
[FIX] point_of_sale: ok this one should be good
[MERGE] l10n_be: add translation of belgian chart of accounts in Flemish

requires merge 5049 in server 7.0 (support of i18n_extra folder)
requires l10n_multilang preinstalled before l10n_be (to add translatable fields)
move l10n_be_wizard.yml to l10n_be_hr_payroll_account (requires an accounting plan installed to import data)
set action wizard for multichart selection opened
add translation of chart of account into nl_BE, courtesy of Geert Janssens
point_of_sale: fix default journal selection for config (broken runbot test)