Bug 847975 - [MMS][SMS] remove use of "dtf" and "_" aliases from SMS

1. Fixes the unnecessary deps on dtf and _
2. Readability nits
3. Bug fix


https://bugzilla.mozilla.org/show_bug.cgi?id=847975

```
passes: 29
failures: 0
duration: 2.16s

[sms] SMS App Unit-Test
    [sms] Threads-list
        [sms] Threads-list rendering
            [sms] Check HTML structure1ms ‣
            [sms] Render unread style properly0ms ‣
            [sms] Update thread with contact info0ms ‣
        [sms] Threads-list edit mode
            [sms] Check edit mode form0ms ‣
            [sms] Select all/Deselect All buttons2ms ‣
    [sms] Messages given a thread
        [sms] Thread-messages rendering (bubbles view)
            [sms] Check HTML structure1ms ‣
            [sms] Check message status & styles0ms ‣
            [sms] Check input form & send button5ms ‣
        [sms] Thread-messages Edit mode (bubbles view)
            [sms] Check edit mode form1ms ‣
            [sms] Select/Deselect all2ms ‣
    [sms] URL Links in SMS
        [sms] #Test URL in message2ms ‣
        [sms] #Test URL with phone, email in message1ms ‣
[sms] Utils
    [sms] Utils.escapeHTML
        [sms] valid0ms ‣
        [sms] invalid2ms ‣
    [sms] Utils.getDayDate
        [sms] (UTSMS)0ms ‣
    [sms] Utils.getHeaderDate
        [sms] (today [String|Number|Date])1ms ‣
        [sms] (yesterday [String|Number|Date])1ms ‣
    [sms] Utils.getPhoneDetails
        [sms] (number, contact, callback)5ms ‣
        [sms] (number, null, callback)1ms ‣
        [sms] (number (wrong number), contact, callback)31ms ‣
        [sms] (number, contact (blank name), callback)4ms ‣
    [sms] Utils for MMS user story test
        [sms] Image rescaling to 300kB0ms ‣
[sms] Contacts
    [sms] Contacts.findByString (success)
        [sms] (string[tel,givenName,familyName], ...) Match7ms ‣
        [sms] (string[tel,givenName,familyName], ...) No Match2ms ‣
        [sms] (string[tel], ...) Match2ms ‣
        [sms] (string[tel], ...) No Match2ms ‣
    [sms] Contacts.findBy (success)
        [sms] (object, ...), Match4ms ‣
        [sms] (object, ...), No Match4ms ‣
    [sms] Contacts.findBy (error)
        [sms] ({}, ...)3ms ‣
```

```bash
rick at arcee in ~/clonez/gaia/apps/sms/js on 847975*
$ glint
Linting: /Users/rick/clonez/gaia/apps/sms/js/action_menu.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/activity_handler.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/blacklist.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/contacts.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/fixed_header.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/link_action_handler-alt.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/link_action_handler.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/link_helper.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/message_manager.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/search_utils.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/sms_mock.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/startup.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/thread_list_ui-alt.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/thread_list_ui.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/thread_ui-alt.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/thread_ui.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/utils.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/js/waiting_screen.js
1 files checked, no errors found.
rick at arcee in ~/clonez/gaia/apps/sms/js on 847975*
$ ..
rick at arcee in ~/clonez/gaia/apps/sms on 847975*
$ cd test/unit/ && glint
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/contacts_test.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/messages_mockup.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/mock_contact.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/mock_l10n.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/sms_test.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/sms_test_html_mockup.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/thread_list_mockup.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/utils_mockup.js
1 files checked, no errors found.
Linting: /Users/rick/clonez/gaia/apps/sms/test/unit/utils_test.js
1 files checked, no errors found.
```


## Smoke Tests

PASS  [CONTACTS] Send an sms from a contact detail - Verify the contact receives the SMS
PASS  [CONTACTS] Launch sms on an existing contact with a phone number in the contacts app and confirm you can send a message
PASS  [SMS] Receive a sms with vibration (device unlocked) & confirm notification - verify that the notification is fired and that you can see the message received from the other phone