Incremental account security

[brunobar79]

Description

Implemented all the functionality from #185 which can be seen here: https://www.figma.com/proto/BDcfanN7wCZqbB446t8szhQy/MetaMask-Mobile?node-id=427%3A0&viewport=-153%2C570%2C0.760407&scaling=scale-down&redirected=1

Checklist

• There is a related GitHub issue
• Tests are included if applicable
• Any added code is fully documented

Extras

• Added the latest version of JSC for android ( https://github.com/react-native-community/jsc-android-buildscripts )
• Added the MetaMask animated fox (iOS only) as an external dep
• Minor version bump of react-native

Issue

Resolves #185

[estebanmino]

This is probably going to take me a while to fully QA it so I'll add comments as I find something new (if I do)

While importing account. When user imports account password is set but if the account has balance the view containing ETH was deposited in your account flow still appears with the first transaction. Moreover this transaction is in Ropsten so I guess it shouldn't start the back up flow. Then if I follow the flow and set a password I get a Invalid password error, I'm guessing is because i already have a password.

[estebanmino]

When Exploring and Log out. If I choose Start exploring now and then I log out, when I go again to Start exploring now I get a different account . I'm thinking in an user that gives the address to a friend to deposit ETH, if the app is logged out or the phone turned off, the user may lost that account and deposit.

[estebanmino]

Protect your funds touchable ( backUp alert ) I didn't find this in Figma, wouldn't we want it in the wallet section as well?

[brunobar79]

RE 1st comment: Good catch! forgot to set the flags on those scenarios. Just fixed it.
Also FYI, I'm running the flow in testnets too, otherwise we would have to pay for testing it.

RE 2nd comment: I'm planning to remove log out for users who didn't set a password before private beta. I'm leaving it for now because it's the only way to try the flow.

RE 3rd comment: It is here: https://www.figma.com/file/BDcfanN7wCZqbB446t8szhQy/MetaMask-Mobile?node-id=36%3A304 (last column)
Personally I think it's enough to be displayed there since the browser is the home screen so users will see it every time they launch the app.

In the wallet it might interfere with tokens / collectibles, etc.

[estebanmino]

All comments addressed, QAed both Android and IOS. Have no comments about the code itself. This PR is awesome!!