test: add e2e signing and ethereum tests

[hanwencheng]

This PR improve current e2e tests.

1. Add more tests for Substrate signing

Now we have two e2e suites: one is for key management and path derivation, the other is for signing test.

e2e/signing.spec.ts
|--Single QR Extrinsic (Sign TX)
|---SetRemark
|---Transfer
|--Multi Part QR Extrinsic(Sign Message)
|---SetRemark

2. Add the Ethereum account tests: generation, deletion, and signing

e2e/signing.spec.ts
-Ethereum
|--Sign Transaction
|--Sign Message

e2e/identityManipulation.spec.ts
-Ethereum
|--Account Creation
|--Account Deletion

3. Reformat project layout for units test and e2e test

previously:

-src
-e2e
-specs
-jest.config.js
...

currently:

-src
-test
 |--e2e
   |---specs
   |---jest.config.js
   |---...
 |--unit
   |---specs
   |---jest.config.js
   |---...
 |--commonConfig.js

Since Detox and Unit test both use Jest as test runner, and they share similar parts of the configs, now move them together into the test folder, which brings a clear structure layout and configuration.

4. How to test

• yarn to upgrade dependencies
• Start react native server by yarn start --reset-cache
• Run yarn e2e:ios to test on ios, and yarn e2e:android for the android test suits. notice: android e2e may be not stable with pin code input, sometime input is missing, just try again will fix the error
• At the same time existed unit test should not be broken yarn unit should succeed.

[hanwencheng]

TODO: Add ethereum account deletion test