Correct appearance issues with Settings popover.

* Height of popover now matches the height of the content in the view
* Explicitly nil accessory views when not used, fixing an error where unexpected accessory views would appear.
[Fix #165] Add caption headings to the picker.
[Bug #164] Disable autocorrect on sensor fields in the Settings popover.
[Bug #164]: Modify next/return button handling while adding a sensor in the Settings popover.

* Address field displays the "URL" keyboard
* "Next" button appears while editing the name field (moves selection to address field)
* "Done" button appears while editing address field (dismisses keyboard)
[Bug #164] Keyboard still visible when pickers in biographical information view are visible.

Note that this animation is somewhat jarring, but a future direction should be to completely remove theses pickers (see bug #112).
[Bug #164] Don't require a name when adding a sensor via the Settings popover.
Swap address field and text field, to be more in line with the device walkthrough and the fact that a name is not required since 3bce5a7e5bdd3ae1bf5be0d5ea8c52b7b1e5775c.
[Bug #164] Make "next" and "done" buttons do something during device setup walkthrough.

Remove some old code to make the keyboard disappear if you tap outside the table.
Move header files into the appropriate directory structure.
[Bug #164] Fix "next" and "done" handling with height/weight field (regression from touch logging).