Update release notes for 4.55

[mokagio]

4.54 was not shipped so we can use its notes in 4.55

[dangermattic]

	1 Message
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[wpmobilebot]

📲 You can test the changes from this Pull Request in Simplenote Prototype Build by scanning the QR code below to install the corresponding build.

	App Name	Simplenote Prototype Build
	Build Number	pr1667-0e67fa3-0192d750-ea31-4daa-9b2e-cd281dd9de4c
	Version	4.55
	Bundle ID	com.codality.NotationalFlow.Alpha
	Commit	0e67fa3
	App Center Build	Simplenote - Installable Builds #392

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