Implement encrypted feedback

briar-android/AndroidManifest.xml

briar-android/res/layout/activity_dev_report.xml

briar-android/res/layout/list_item_crash.xml

briar-android/res/values/strings.xml

briar-android/res/xml/settings_debug.xml

...ndroid/src/org/briarproject/android/AndroidComponent.java

...ndroid/src/org/briarproject/android/BriarApplication.java

...droid/src/org/briarproject/android/DevReportActivity.java

...c/org/briarproject/android/fragment/SettingsFragment.java

.../src/org/briarproject/android/util/BriarReportSender.java

...droid/src/org/briarproject/android/util/UserFeedback.java

...r-android/src/org/briarproject/plugins/tor/TorPlugin.java

...r-api/src/org/briarproject/api/reporting/DevReporter.java

...-core/src/org/briarproject/reporting/DevReporterImpl.java