[FIX] tools.translate: addons path resolution failed with duplicates

When the addons_path config contained the
default path, the system was working with
an empty addons_path in the middle of the
other paths. This empty one matched for all
files, making all files appear to belong to
the root path component, e.g. `home` if the
root path is in /home.
Refactored a bit to avoid duplicates and
redundant path calculations.
[I18N] Update all 7.0 translation templates with latest terms and annotations

Total new terms: 168
Total deleted terms: 95
Total identical terms: 16329
(Some modules skipped, typically all l10n_* modules)
Merge branch '7.0' of https://github.com/odoo/odoo into 7.0-linux64