Add namespace multi level on translation ressources

[Nico0084]

Could use with :

'mynamespace': { 'my-key1' : 'foo1', 'my-key2' : 'foo2' }, 'foonamespace': { 'level2' : { 'my-key1' : 'toto1', 'my_key2' : 'titi2' } } get translation : localize('foonamespace:level2:my-key1')

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