Allows more precise tax rate

Currently, the French tax rate (19.6%) isn't supported, as it is rounded to 0.20 (2 digits scale) in the MySQL field.
Merge pull request #5 from winzou/patch-1

Allows more precise tax rate
Dutch translations
Init polish translation
Init polish translation
Merge pull request #7 from Antek88/master

Init polish translation
Merge pull request #6 from tvlooy/dutch_translations

Dutch translations
Validation groups
Merge pull request #10 from umpirsky/feature/validation-groups

Validation groups
Remove entities
Update composer.json
Move mapping around
Remove default entities, update configuration
Remove useless specs and update relevant ones
add Japanese translation
Move validation groups to separate config tree
Merge pull request #11 from 77web/translation-ja

add Japanese translation
Merge pull request #9 from Sylius/symfony-2-3

[WIP] Symfony 2.3 upgrade
Fix branch alias
Handle default models via listener