[FIX] l10n_fr: 2014 tax update patch has removed obsolete templates, causing an error at module update
      
Due to the relationship between fiscal position
templates and tax templates, the removal of
obsolete tax templates may crash if the corresponding
fiscal positions are not deleted before.
In a recent l10n_fr patch [1] a number of
templates disappeared, which causes an error during
subsequent updates on databases where the obsolete
templates are still present.
      
As a workaround, we can force a deletion of
all fiscal position templates before loading
them. This is relatively safe because the templates
are not connected to live data, and will be
re-created during the update (except for the
obsolete ones which will be gone forever).

[1] addons 7.0 rev 9515 rev-id: odo@openerp.com-20131010114424-atzr3bl9e9diir2g