Add linter for strings attribute names

Only one bad example for now, which is a misspelling that's not
entirely uncommon and can lead to real problems (see linked bug).

Example output:
Line 58: 'my_new': Misspelled <string> attribute.
        Actual: translateable
        Example: translatable

Bug: 119884572
Test: with a misspelled attribute
Change-Id: If61412fe318a34191920781c4834584363080e11