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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