Enable module stability support

[dive]

In order to support module stability feature, I switched Chatto & ChattoAdditions to Swift 5 source compatibility mode and enabled BUILD_LIBRARY_FOR_DISTRIBUTION option for release configurations.
There are no logical changes, also, I did not touch some generic warnings.

[codecov-io]

Codecov Report

Merging #625 into master will decrease coverage by 0.03%.
The diff coverage is 74.07%.

@@            Coverage Diff             @@
##           master     #625      +/-   ##
==========================================
- Coverage   60.73%   60.69%   -0.04%     
==========================================
  Files          92       92              
  Lines        4892     4898       +6     
==========================================
+ Hits         2971     2973       +2     
- Misses       1921     1925       +4

Impacted Files	Coverage Δ
...BaseChatViewController+AccessoryViewRevealer.swift	0% <ø> (ø)	⬆️
.../Chat Items/BaseMessage/BaseMessageViewModel.swift	89.65% <100%> (ø)	⬆️
ChattoAdditions/Source/Common/AnimationUtils.swift	100% <100%> (ø)	⬆️
...ws/BaseMessageCollectionViewCellDefaultStyle.swift	96.47% <100%> (ø)	⬆️
...ditions/Source/Common/UIEdgeInsets+Additions.swift	100% <100%> (ø)	⬆️
...s/PhotoMessageCollectionViewCellDefaultStyle.swift	84.09% <100%> (ø)	⬆️
...ttoAdditions/Source/Common/UIColor+Additions.swift	100% <100%> (ø)	⬆️
...ws/TextMessageCollectionViewCellDefaultStyle.swift	91.78% <100%> (ø)	⬆️
.../Input/Photos/Camera/LiveCameraCellPresenter.swift	80.41% <33.33%> (-1.51%)	⬇️
...ttoAdditions/Source/Common/UIImage+Additions.swift	30.3% <33.33%> (ø)	⬆️
... and 2 more

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