Cleanup Gradle and Proguard to fix connectedCheck

Closes #597

See merge request !284

Merge branch '311-audit-crash-report-and-feedback-fields-for-sensitive-or-identifying-information' into 'master'

Remove sensitive information from crash and feedback reports

This depends on MR !290 and removes also the crash report settings.

Closes #311

See merge request !291

Scrub addresses before logging them

MAC, IP and onion addresses are now scrubbed before logging to ensure we don't leave any sensitive information in plaintext on the device or send it in crash reports or feedback.

* Bluetooth MAC addresses keep the first and last octets
* IPv4 addresses keep the first and last octets
* IPv6 addresses should be scrubbed completely (couldn't test)
* Onion addresses keep the first three characters

If an address is invalid it will not be scrubbed to enable debugging, because it is most likely not sensitive.

Closes #592

See merge request !290

Closes #311

Add feed title to imported entries

Also fixes one bug where a new feed was not saved and improved HTML stripping a bit.

Closes #483

See merge request !287

This also fixes a bug where new feeds was not added properly.

Also fixes one bug where a new feed was not saved and
improved HTML stripping a bit.

Upgrade gradle to 2.14.1 and gradle plugin to 2.1.3.



See merge request !292

Add hidden service address for dev reports

Closes #573

See merge request !289

Server-side code for accepting crash reports and feedback

* Moved some shared code for copying InputStreams to OutputStreams into a utility class
* Modified the  dev report sender to send one report per connection
  * Easier to handle on the server side
  * If the connection fails after sending any reports, they don't need to be resent
  * Tor will reuse the circuit, so it's cheap
* Added server-side code for accepting dev reports
  * We need to protect the server's resources from DoS attacks
  * Reports can't be larger than 1 MB
  * Connections are limited to an average rate of one per minute
  * The rate limiter uses a token bucket to allow bursts of up to 1,000 connections
  * If the rate limit is exceeded, connection attempts will fail - clients will retry next time they sign in
  * The limits can be raised when we move to a bigger server (and when we have some users)


See merge request !288

Stop supporting Gingerbread

Closes #566

See merge request !278

This allows simpler server-side code, and a failure part-way through sending won't require restarting from the beginning next time.

Fix two crashes when scanning QR codes

One crash was two due the `Context` being `null` and the other due to the camera being opened within an `AsyncTask`.

Closes #583

See merge request !282

Add introduced contacts as UNVERIFIED

This MR **breaks** the database schema requiring you to create a new account.

Closes #580

See merge request !280

Also, don't support unverifying contacts.

Closes #580

Validate New Messages for Reblogging and Comments of Blog Posts

Closes #591

See merge request !279

Also includes unit tests for the new message types.

Closes #591

Let clients decide whether to share messages or not

Before this MR, the `ValidationManager` was sharing all messages after they had been delivered. Now, it is within the client's responsibility whether to share messages or not. So far, only the Blog and the Forum client are sharing incoming messages.

Closes #595

See merge request !283

Group strings and remove unused resources

Before I grouped the strings, I removed unused resources as well to not group things that are not being used anymore.

The grouping tries to follow a normal usage lifecycle of the app where the user works their way down the navigation drawer and explores all features in one area.

Closes #342

See merge request !277

Also properly handle back navigation when trying to add contacts.

Don't try to reuse already bound ports for key agreement

This is one cause of #447, but probably not the only one.

See merge request !281