[SSK] Fix disappearing messages don't become consistent after reinstall

Fixes the bug wherein:

Given the sender had disappearing messages enabled
And the receiver thinks it's disabled (this can happen due to re-install)
When we receive a disappearing message
The message does start expiring timer and disappear
But you see a notice "<sender> disabled disappearing messages"
Rather than the expected "<Sender> set disappearing messages timer to X".

// FREEBIE

Handle key change in group send

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Handle key change in group send

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Explain send failures for text and media messages

fixes signalapp#1231

Motivation
----------
Previously when messages failed to send, there was no reason given.
Furthermore, when media messages failed to send there was no indication
that any attempt to send the message even occurred, nor a retry
dialog.

UX Changes
----------
- Show "uploading" status for media
- Show specific error message in retry-send dialog
- Only scroll to bottom when new message is inserted
- Show specific errors when group creation fails

Code Changes
-----------
- Updated incorrect references to TSMessageAdapters which were actually
  references to OWSMessageData
- MessageSender was extracted from SSK MessagesManager
- access MessagesManager as property
- idiomatic init/properties for Env
- log contact intersections
- Move scroll-to-bottom animation to main thread.

// FREEBIE

Explain send failures for text and media messages

fixes signalapp#1231

Motivation
----------
Previously when messages failed to send, there was no reason given.
Furthermore, when media messages failed to send there was no indication
that any attempt to send the message even occurred, nor a retry
dialog.

UX Changes
----------
- Show "uploading" status for media
- Show specific error message in retry-send dialog
- Only scroll to bottom when new message is inserted
- Show specific errors when group creation fails

Code Changes
-----------
- Updated incorrect references to TSMessageAdapters which were actually
  references to OWSMessageData
- MessageSender was extracted from SSK MessagesManager
- access MessagesManager as property
- idiomatic init/properties for Env
- log contact intersections
- Move scroll-to-bottom animation to main thread.

// FREEBIE

WIP beta build.

There are still some issues to work out, but want to get a build
approved before the weekend approval queue takes place.

// FREEBIE

WIP beta build.

There are still some issues to work out, but want to get a build
approved before the weekend approval queue takes place.

// FREEBIE

Fix slow reloading conversation view. (signalapp#1397)

Fix animation memory leak exacerbated every time you reload a
conversation with expiration timers.

Stop animation on cells that aren't currently being displayed. This is
relatively minor compared to the above, but still, no reason to waste
cycles.

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Fix empty bubble when setting disappearing message timer in a thread to

yourself.

fixes signalapp#1393

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Fix hidden incoming audio

Missed bottom constraint when customizing incoming message bubbles to
include timer icon in footer.

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