Release 15.1.0

• Merge pull request #101 from kanzitelli/rn-0.70 (ef37f6c)
• hermes removed from Embed Frameworks (39e4916)
• Update README.md (12fc55d)
• rn 0.70 integration (4f0595c)
• rn0.70 patch file (61dbafe)
• rn-ui-lib fix with update (a4bce9f)
• packages update (614e73b)
• Update .gitignore (cb5d423)
• mobx observer(...) is screen based (33007c9)