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closes #2422

- updated to use new change password method
- have all save settings use notifications
- create assetSrc helper for creating asset paths with subdir's properly
 prefixed
Gonna stick with `assetSrc` as it's explicit about what it returns.  For example in the future we may want to have a generic asset helper that lets you just put in a string name and it gives you an object that has the src and the size of the image.  Easier to start specific.