Refactor Integration Tests

This is quite a massive MR (currently 1763 additions and 3482 deletions). However, there's not so much happening. The only thing I did was moving redundant code from the various protocol integration tests to the `BriarIntegrationTest` class.

All integration tests are still passing.

Closes #727

See merge request !433

Add unit tests for group validators

Part of #766

See merge request !436

Add unit tests for group invitation client

Part of #766

See merge request !429

Fix Contacts Item always beeing selected if Back is pressed in the NavMenu

Signed-off-by: goapunk <noobie@goapunks.net>

Closes #782

See merge request !438

Signed-off-by: goapunk <noobie@goapunks.net>

Select the correct MenuItem when Back is pressed in NawDrawer

Signed-off-by: goapunk <noobie@goapunks.net>

Closes #782

See merge request !437

Bring back the toolbar shadow

![device-2016-11-21-180111](/uploads/7cd5e6a1e7a4b79b6d7cf81377b148a0/device-2016-11-21-180111.png)

Closes #477

See merge request !431

Signed-off-by: goapunk <noobie@goapunks.net>

Make navigation drawer scrollable

![device-2016-11-22-095642](/uploads/bcd5f68d40816ed2e44c3194eb977695/device-2016-11-22-095642.png)![device-2016-11-22-095658](/uploads/da1807e981632936ba04db24dc7b8ae7/device-2016-11-22-095658.png)

Closes #666

See merge request !432

Make dialog actions consistent

Closes #504

See merge request !430

Use uuid created from the commitment/payload instead of the uuid returned from getUuid()

Signed-off-by: goapunk <noobie@goapunks.net>

Closes #774

See merge request !435

Signed-off-by: goapunk <noobie@goapunks.net>

Remove injected field from unit test

Getting this off my todo list...

Closes #747

See merge request !428

Make original author look like commenter when reblogged

This wasn't as simple as changing the persona in the XML,
because the same layout is used for a post whether reblogged or not.
So the persona needs to be changed programmatically for reblogged posts.
For this, the `AuthorView#setPersona()` method has been made public and
was changed to always set all views into the desired state to support
usage in a RecyclerView.

![device-2016-11-21-094221](/uploads/e508937ad2d2d84f97f5be29bdeaac2e/device-2016-11-21-094221.png)

Closes #639

See merge request !426

Fix KeyAgreement after regression

Closes #768

See merge request !427

This wasn't as simple as changing the persona in the XML,
because the same layout is used for a post whether reblogged or not.
So the persona needs to be changed programmatically for reblogged posts.
For this, the `AuthorView#setPersona()` method has been made public and
was changed to always set all views into the desired state to support
usage in a RecyclerView.

make TextInputView resizable again

* TextInputView can resize up to 3 lines again

Signed-off-by: goapunk <noobie@goapunks.net>

Closes #762

See merge request !425

* TextInputView can resize up to 3 lines again

Signed-off-by: goapunk <noobie@goapunks.net>

Remove old signature class from API

I decided not to remove the SignatureImpl class, as it's not a trivial wrapper around the Bouncy Castle class, but I moved the interface into briar-core and made it  package-private.

Closes #763

See merge request !424

Introduce a @Scheduler annotation

and make sure work is offloaded to an executor, so exceptions can be caught.

Closes #524

See merge request !422

Remove Device ID

Closes #757

See merge request !423