FreeNAS Code

use lazy ugettext for models/forms + add forgotten strings to i18n

use lazy ugettext for navtree

improvements in navtree to avoid code/config duplication

change custom tree node types for code cleanup (js)

i18n support for the rest of tabs/menu tree

first pass in not exposing _children tree attribute

temporary transition of the way a tree node children are treated

replace navtree methods to use the new tree classes

tests for basic sharing views

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