Strengthen relation between welcome and app menu

[Cris Dywan]

Currently the welcome screen is very helpful, but after having added one contact, it may be unclear to the casual user how to continue performing the same actions.

icon + Import (+ low contrast subtitle) → app menu, Import from vCard, no icon

Due to the low contrast text, the user may fail to read the hint and simply proceed importing. Afterwards he can't find the same icon and he doesn't realise that vCard is the same thing.

Possible improvements:
- use the same icon
- increase contrast in Elementary theme
- use the same label for both welcome screen and app menu

icon + Create (+ low contrast subtitle) → Add icon

The icons are different. The icon means Add, so it isn't obviously connected to Create.

Possible improvements:
- use the same icon
- change label to Add Contact
- make the toolbar button "important" so a label is shown

[Danielle Foré (danrabbit)]

Some of these ideas I agree with, some not so much.

Importing:
* Yes it could use the same icon (address-book-insert)
* This has already been done in eGTK's bzr branch
* It might be helpful to change the hint text from "add a vCard" to "Import a vCard" but having "Import from vCard" and then "Import a vCard from your hard drive" below would be kind of needlessly repeating ourselves.

Creating:
* Yep, again same icon is a good idea. (contact-new)
* I wouldn't change the language to "add" I would definitely keep it "create" because you're not adding from an external source, you are creating it within Dexter itself.
* Personally I'm against have such labels in the toolbar, but keep in mind that this won't affect users with "only icons" in the toolbar anyways. So it may not really be helpful at all.